Templar Assassin
* All of Jakiro's active skills can be targeted on an area, which is effective at forcing Templar Assassin to move should she 
Meld away.
* Many of Jakiro's spells utilize damage-over-time mechanics, which makes it easy to strip away layers of 
Refraction.
Naga Siren
* Jakiro's damage over time abilities can clear Naga Siren's illusions and can hurt real Naga Siren even for the duration of 
Song of the Siren.
* Naga Siren is not a hero that likes to go for 
Black King Bar, and that makes her very vulnerable to Jakiro's damage over time in every phase of the game.
Additional:
* Jakiro's damage over time abilities can clear Naga Siren's illusions and can hurt real Naga Siren even for the duration of Song of the Siren.
* Since Naga Siren is a hero who barely goes for Black King Bar, this can make her very vulnerable to Jakiro's damage over time in every phase of the game.
Templar Assassin
* Batrider's DoT damage quickly removes Templar Assassin's Refraction and can damage her during Meld.
Additional:
* Batrider's abilities are designed to deal damage over time, burning through Templar Assassin's layers extremely quickly. 
Flamebreak applies 7 instances of damage, burning through the entirety of Refraction, and 
Firefly applies damage on the place, forcing her to either get out of Meld and be attacked or stay in place or be incinerated.
* 
Flaming Lasso pierces Black King Bar and rendering Templar Assassin helpless unless there are allies helping her.
Naga Siren
* Many stacks of 
Sticky Napalm, combined with Flamebreak and Firefly, allows Batrider to destroy illusions from 
Mirror Image.
* If Batrider can manage to destroy all illusions from Naga Siren, he will be able to use Flaming Lasso on the real one, and will be able to drag her toward his team, potentially preventing Naga Siren from escaping with Song of the Siren.
Additional:
* Many stacks of Sticky Napalm, combined with Flamebreak and Firefly, allows Batrider to destroy illusions from Mirror Image.
* If Batrider can manage to destroy all illusions from Naga Siren, he will be able to use Flaming Lasso on the real one, and will be able to drag her toward his team, potentially preventing Naga Siren from escaping with Song of the Siren.
Templar Assassin
* Searing Chains and Flame Guard quickly burn through Refraction instances exposing her low health pool.
* Templar Assassin has no inherent way to prevent Ember Spirit from escaping, a good Ember player also will be able to dodge her meld attack
* Ember Spirit`s 
Searing chains give true sight into invisibility, why Templar Assassin can't hide from it in Meld and get out of the fight using 
Blink Dagger
Additional:
* 
Flame Guard burns quickly through Refraction charges, which is why it can interrupt Templar Assassin, giving his team the opportunity to kill her.
* Ember Spirit can dodge a blow from Meld with 
Sleight of fist, providing him an advantage in a 1v1 situation.
* Searing Chains give true sight into invisibility, why Templar Assassin can't hide from it in Meld and get out of the fight using Blink Dagger.
Naga Siren
* Heroes that heavily depend on illusions or summons, (
Naga Siren, 
Terrorblade, 
Phantom Lancer, 
Lycan,...) are vulnerable to Sleight of Fist and even more so if Ember Spirit has 
Battle Fury.
Templar Assassin
* Ion Shell destroys Refraction's protection stacks in short time.
* Surge ignores the massive slow from 
Psionic Trap.
Naga Siren
* Heroes that rely on illusions typically spawn very strong illusions inside Dark Seer Wall of Replica that he can use against them or their team: Phantom Lancer, 
Chaos Knight, Naga Siren, Terrorblade.
Templar Assassin
* Sand King can quickly remove her Refraction with his Sand Storm.
* Once Refraction is down, she is very vulnerable to Epicenter's high magic damage.
Naga Siren
* Since Naga Siren is a hero who barely goes for Black King Bar, she is vulnerable to nukers with strong magical damage and big area-of-effect spells in every game more than any other carry heroes: 
Sand King, 
Jakiro, 
Leshrac, 
Lina, 
Earthshaker, 
Zeus.
Templar Assassin
* 
Focus Fire tears apart Templar Assassin's Refraction very quickly and easily bursts her down due to her low health pool against Windranger's immense attack speed.
* Templar Assassin's Psionic Trap doesn't slow down Windranger due to 
Windrun. Additionally, Windranger can survive Templar Assassin's high burst damage thanks to the evasion it provides.
Naga Siren
* As long as Windranger is able to identify the real hero among the illusions, heroes relying on them can be easily tagged with Focus Fire: Chaos Knight, Terrorblade, Phantom Lancer, Naga Siren.
Templar Assassin
* Despite the armor reduction from Meld, Templar Assassin's reliance on physical damage and medium attack speed is unlikely to harm Dragon Knight.
* Templar Assassin's Refraction charges also get quickly removed by the damage over time from Dragon Knight's ultimate.
Additional:
* The damage over time from Dragon Knight's 
Elder Dragon Form rapidly burns down Refraction, allowing him to attack her.
* Also, 
Breathe Fire reduces Templar Assassin's damage and 
Dragon Tail is a stun with a considerable duration, letting him and his team whittle her health down once her defenses wear off.
* Templar Assassin will struggle to kill Dragon Knight thanks to his high armor and health regen from 
Dragon Blood as she deals entirely physical damage.
Naga Siren
* Heroes whose attacks can affect multiple enemies at once will clear Naga Siren's illusions. Such heroes include 
Sven, 
Magnus, 
Dragon Knight, 
Luna, 
Medusa, 
Templar Assassin, 
Gyrocopter, 
Muerta.
Templar Assassin
* Weak damage but high tick rate or persist in a long time: 
Slark, Gyrocopter, 
Queen of Pain, 
Shadow Shaman (
Shackles), Jakiro, 
Pugna, 
Doom
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: 
Meepo, 
Witch Doctor, Lycan, 
Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her 
Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna, Doom
Naga Siren
* 
Flak Cannon and 
Call Down can easily clear Naga Siren's illusions.
Templar Assassin
* 
Blade Fury's damage over time dispels Refraction almost instantly.
* Juggernaut's high armor allows him to survive for long enough to remove Refraction and threaten her with 
Omnislash as long as he or his team carries detection.
* Templar Assassin's short attack range makes it difficult for her to target a well-placed 
Healing Ward. She cannot splash onto it with 
Psi Blades.
Naga Siren
* Blade Fury offers good AoE damage to clear illusions and can hurt the real Naga Siren as well if she chooses to blend in the illusions. 
Diffusal Blade does nothing to Juggernaut either when he uses Blade Fury.
* 
Aghanim's Shard upgraded Blade Fury along with Lv 20 DPS talent will shred all illusions almost instantly, especially when combined with 
Mjollnir, a common item for Juggernaut.
Naga Siren
* Illusion-based heroes are effective against Omnislash and Juggernaut's single-targeted damage: Naga Siren, Chaos Knight, Terrorblade,Phantom Lancer.
Templar Assassin
* Heroes with invisibility will be detected by Thirst when they have low enough health: 
Bounty Hunter, Templar Assassin, 
Riki, 
Clinkz, 
Weaver, 
Treant Protector, 
Nyx Assassin.
Naga Siren
* Heroes with long-lasting, undispellable debuffs will pinpoint the true Naga Siren: 
Spirit Breaker, 
Bloodseeker, Witch Doctor.
Templar Assassin
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna, Doom
Naga Siren
* Heroes with AoE nukes will clear her illusions in no time, especially if they are percentage-damage-based, like 
Underlord's 
Firestorm, 
Elder Titan's 
Earth Splitter, Enigma's 
Midnight Pulse, Zeus's 
Arc Lightning, Jakiro's 
Liquid Frost from Aghanim's Shard etc.
Templar Assassin
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna, Doom
Naga Siren
* Naga Siren's Song of the Siren may be useful but Poof will destroy all of her illusions.
Templar Assassin
* Any hero who lanes very poorly will struggle with Primal Beast's potential snowball in the very early levels, like 
Keeper of the Light, Luna, Templar Assassin...
Naga Siren
* Illusion heroes will struggle against Primal Beast's area damage capability, such as Chaos Knight, Naga Siren, Terrorblade.
Naga Siren
* Axe will destroy her illusions by proccing 
Counter Helix more often due to him being hit by more attacks.
Templar Assassin
* Shackles and Mass Serpent Ward instantly destroy Refraction
Templar Assassin
* Templar Assassin is dependant on Refraction in teamfights. Because Magnetize deals damage per second and Earth Spirit is even able to refresh the duration of his ultimate he is suitable for wasting Refraction and allowing his team to take her down.
Templar Assassin
* The damage block instances of Refraction can be burned down with Ignite.
* Fire Shield effectively reduces the burst damage from a Meld-charged ambush from Templar Assassin, provided the spell is cast beforehand.
Templar Assassin
* The three Primal Split brewlings all attacking Templar Assassin at once will remove her Refraction quickly, especially with Fire's Permanent Immolation.
* Templar Assassin has no way to stop Brewmaster from using Primal Split by herself, and may get unlucky and miss her Meld if trying to burst him during her ally's disable.
Naga Siren
* Dawnbreaker can easily clear waves of Naga Siren's illusions from Mirror Image with 
Starbreaker, 
Celestial Hammer and 
Solar Guardian.
* Aghanim's Shard upgraded Starbreaker will allow Dawnbreaker to dispel Ensnare and freely attack Naga Siren during Song of the Siren when combined with Black King Bar, a common item on Dawnbreaker.
* Solar Guardian allows Dawnbreaker to counter any attempts of Naga Siren and rejoin her team with Solar Guardian when they require it. 
Aghanim's Scepter upgraded Solar Guardian can also give Dawnbreaker's allies evasion while Dawnbreaker is airborne for it's duration, as Naga Siren mainly relies on direct attacks in order to deal damage.
Additional:
* Dawnbreaker can easily clear waves of Naga Siren's illusions from Mirror Image with Starbreaker, Celestial Hammer and Solar Guardian.
* Aghanim's Shard upgraded Starbreaker will allow Dawnbreaker to dispel Ensnare and freely attack Naga Siren during Song of the Siren when combined with Black King Bar, a common item on Dawnbreaker.
* Solar Guardian allows Dawnbreaker to counter any pushing attempts of Naga Siren and rejoin her team with Solar Guardian when they require it. Aghanim's Scepter upgraded Solar Guardian can also give Dawnbreaker's allies evasion while Dawnbreaker is airborne for it's duration, as Naga Siren mainly relies on direct attacks in order to deal damage. Solar Guardian can also be used after Naga Siren uses Song of the Siren near her allies to either escape from or counter-initiate against them.
Templar Assassin
* His 
Rot can force Templar Assassin out of her Meld and destroy all of her Refraction charges quickly, and her small health pool and meager defense make her very vulnerable to his 
Meat Hook without Refraction.
Templar Assassin
* Pugna's 
Decrepify can render Templar Assassin's physical attacks useless.
* Pugna can also cast 
Life Drain on Templar Assassin, burning her Refraction instances.
* On the other hand, Pugna generally has low health and armor. Use this to your advantage.
Templar Assassin
* Heroes that have disposable area-targeted spells can force her to undo her Meld: Leshrac, 
Puck, 
Tiny, Jakiro,. An experienced Templar Assassin could try to use Refraction before Meld so she can tank through those damage without getting her Blink disabled.
Naga Siren
* Avalanche and Toss combo makes short work of Mirror Image's illusions.
* Tiny's cleave with Tree Grab and area of effect damage with Tree Volley will easily wipe out illusions.
Templar Assassin
* Due to Tiny's non-existent agility gain, high physical damage heroes are more effective against him (Clinkz, Templar Assassin, 
Ursa, 
Wraith King etc).
Templar Assassin
* 
Bushwhack can tear through Refraction as it does multiple intervals of damage.
Naga Siren
* 
Mortimer Kisses can make quick work of Naga Siren's illusions.
* 
Scatterblast and 
Firesnap Cookie's AoE damage are also decent ways to deal with Naga's illusions.
Templar Assassin
* Phantom Lancer's illusions destroy Refraction charges very quickly.
* Diffusal Blade, his core item, drains Templar Assassin's small mana pool, rendering her unable to save herself with Meld.
Additional:
* Phantom Lancer's illusions destroy Refraction charges very quickly.
* Diffusal Blade, his core item, drains Templar Assassin's small mana pool, rendering her unable to save herself with Meld.
Naga Siren
* 
Waveform clear Mirror Image illusions from Naga Siren. And though Ensnare can prevent Morphling from using Waveform to escape, he can easily dispel it with 
Manta Style, a common item on Morphling.
* 
Morph allows Morphling to copy Naga Siren's abilities and combine them with Manta Style, a commong item for Morphling, to destroy Naga Siren's illusions. Aghanim's Scepter upgraded Morph also allows Morphling to create a strong illusion of Naga Siren that can do the same and which can also allow Morphling to close the gap on Naga Siren.
Templar Assassin
* Attacks from Boars and the attack speed boost from Inner Beast will quickly wear down Refraction.
Templar Assassin
* Firestorm will destroy Refraction charges very quickly.
* Firestorm will hit Templar Assassin while under the effects of Meld Meld.
* Templar Assassin has a hard time maneuvering around Pit of Malice.
* 
Atrophy Aura weakens Templar Assassin's damage output, as she relies on direct attacks to be effective.
* However, Templar Assassin's Psionic Traps can be used to intercept Underlord and his team, and to keep her team alerted on Underlord if he chooses to use 
Fiend's Gate to get to a designated point of the map.
Naga Siren
* Atrophy Aura makes it hard or Naga Siren to farm on lane and damage Underlord with 
Rip Tide in teamfights. And her only way to counter this is by playing Nuker role.
* Firestorm is very useful for clearing Naga Siren's illusions from Mirror Image and Manta Style.
* However, Naga Siren can catch Underlord and his team unprepared with Song of the Siren if he chooses to use Fiend's Gate to get to a designated point of the map. Naga Siren can also prevent escaping with Fiend's Gate with Ensnare and 
Reel In from Aghanim's Scepter.
Additional:
* Atrophy Aura makes it hard or Naga Siren to farm on lane and damage Underlord with Rip Tide in teamfights. And her only way to counter this is by playing Nuker role.
* Firestorm is very useful for clearing Naga Siren's illusions from Mirror Image and Manta Style.
* However, Naga Siren can catch Underlord and his team unprepared with Song of the Siren if he chooses to use Fiend's Gate to get to a designated point of the map. Naga Siren can also prevent escaping with Fiend's Gate with Ensnare and Reel In from Aghanim's Scepter.
Templar Assassin
* Heroes that provide vision will see Fiend's Gate coming: 
Techies, Templar Assassin, Treant Protector.
Naga Siren
* Heroes with strong area-of-effect damaging and/or disabling abilities will be able to intercept Underlord and his team when they exit from Fiend's Gate: Luna's Aghanim's Scepter upgraded 
Eclipse, 
Dawnbreaker's Solar Guardian, 
Axe's 
Berserker's Call, 
Mars's 
Arena of Blood, Jakiro's 
Macropyre, 
Dual Breath and 
Ice Path, Naga Siren's Song of the Siren, 
Razor's 
Eye of the Storm and 
Plasma Field, Lina's 
Light Strike Array, 
Broodmother's 
Spinner's Snare from Aghanim's Scepter, Elder Titan's Earth Splitter and 
Echo Stomp, 
Alchemist's 
Unstable Concoction and 
Acid Spray, Queen of Pain's 
Sonic Wave, 
Dark Seer's 
Wall of Replica and 
Vacuum, 
Venomancer's 
Noxious Plague and 
Poison Nova from Aghanim's Scepter, 
Oracle's 
Fortune's End and 
Rain of Destiny from Aghanim's Shard, Bloodseeker's 
Blood Rite, Enigma's 
Black Hole and Midnight Pulse, 
Shadow Fiend's 
Requiem of Souls, 
Batrider's Aghanim's Scepter upgraded Flaming Lasso, Firefly, Flamebreak and Sticky Napalm, 
Ancient Apparition's 
Ice Blast, Sand King's 
Epicenter, 
Sand Storm and 
Burrowstrike, Gyrocopter's Call Down, 
Ember Spirit's Sleight of Fist, 
Death Prophet's 
Exorcism and 
Silence, 
Monkey King's 
Wukong's Command, 
Crystal Maiden's 
Freezing Field, Muerta's 
The Calling, Medusa's 
Stone Gaze, Zeus's 
Nimbus from Aghanim's Scepter. 
Dark Willow's 
Bramble Maze, 
Pangolier's 
Swashbuckle, 
Grimstroke's 
Soulbind, 
Ink Swell and 
Stroke of Fate, Earthshaker's 
Echo Slam and 
Fissure, Puck's 
Dream Coil and 
Waning Rift, 
Winter Wyvern's 
Winter's Curse, Magnus's 
Reverse Polarity.
Naga Siren
* Heroes with AoE nukes will clear her illusions in no time, especially if they are percentage-damage-based, like Underlord's Firestorm, Elder Titan's Earth Splitter, Enigma's Midnight Pulse, Zeus's Arc Lightning, Jakiro's Liquid Frost from Aghanim's Shard etc.
Templar Assassin
* Many physical-only single-target heroes like 
Lifestealer, Sven, Wraith King, 
Phantom Assassin, Templar Assassin can have their damage mitigated by Cold Embrace.
Templar Assassin
* With Aghanim's Scepter, Broodmother will gain access to Spinner's Snare, which will allow her to create invisible lines on her webs from 
Spin Web that will root, deal damage over time, and reveal enemy heroes if they unwittingly step on them. This allows Broodmother to keep her allies alerted on heroes who rely on invisibility-themed and movement-themed abilities and items to surprise enemy heroes and disrupt ganking attempts of enemy heroes: Phantom Assassin, Nyx Assassin, 
Mirana, Bounty Hunter, Templar Assassin, Riki, Spirit Breaker, 
Anti-Mage, 
Tusk, Ursa, 
Nature's Prophet, Enigma, 
Void Spirit, Magnus etc.
Naga Siren
* Heroes with long cast animations can be continuously interrupted by Battery Assault: 
Centaur Warrunner, Jakiro, Leshrac, Naga Siren, Underlord.
Templar Assassin
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna, Doom
Naga Siren
* Heroes with long-lasting, undispellable debuffs will pinpoint the true Naga Siren: Spirit Breaker, Bloodseeker, Witch Doctor.
Templar Assassin
* Fragile supports with low armor are always a good prey, also her Psionic Trap will wear down most attempts to flee with their built-in disables: 
Silencer, Crystal Maiden, 
Warlock, Ancient Apparition, Grimstroke, Witch Doctor
Templar Assassin
* Because Templar Assassin does not have escape potential in lane, any support hero with roaming potential and a 
Dust of Appearance can be great at shutting her down early game: 
Earth Spirit, Spirit Breaker, Tusk, Bounty Hunter, Riki, Warlock.
Naga Siren
* Heroes with long-lasting, undispellable debuffs will pinpoint the true Naga Siren: Spirit Breaker, Bloodseeker, Witch Doctor.
Naga Siren
* Heroes with summons and illusions as Spirit Breaker has no strong AoE capabilities to deal with them: Chaos Knight, Phantom Lancer, Terrorblade, Naga Siren, Broodmother, Warlock, 
Visage, Nature's Prophet, Shadow Shaman, Lycan, Wraith King.
Templar Assassin
* Her Refraction charges can and will be easily burned away by Phoenix's damage over time abilities, and Meld can't protect her from Phoenix's AoE abilities, even without detection.
Additional:
* Phoenix's abilities target and deals damage over time, making them a threat against Meld and Refraction. His abilities' nature makes them pretty hard to correctly land on the target, but that is not a problem against a Templar Assassin that needs to stand still during Meld.
* 
Icarus Dive allows Phoenix to shrug off the slow from her trap and make an easy escape from her ambush.
* As Templar Assassin relies on her quality-over-quantity bursting attacks to make quick work on fragile target, 
Fire Spirits' attack speed reduction can cripple her ability to deals any damage during combat. With the debuff applied in early-mid game, a Meld-breaking hit from her is significantly slowed to the point that her target can travel a safe distance before she even lands the hit.
* 
Sun Ray has a quick damage tick and will burn through her Refraction in no time.
* 
Supernova deals damage over time in an incredibly large area, and again with her quality-over-quantity style, she may not be able to attack quickly enough to break through the Phoenix Sun by herself. (not to mention the debuff from Fire Spirits) This can lead to a failed ganking attempt or even a turnaround.
Naga Siren
* Sand King and 
Phoenix have many tools to deal with multiple enemies at once, which will work well against a crowd of illusions.
Naga Siren
* Song of the Siren does not affect Supernova, which allows her and her team to focus the egg while the enemy team is affected by sleep.
* Phoenix cannot use Icarus Dive for escaping when rooted by Ensnare.
* However, Phoenix has many area-of-effect abilities that allow him to clear Naga Siren's illusions from Mirror Image.
Templar Assassin
* Templar Assassin's Refraction will easily be removed by Eye of the Storm, and Static Link reveals Templar Assassin hiding with Meld and drain the bonus damage from Refraction.
Additional:
* Razor's Eye of the Storm damage-over-time easily wear off Refraction charges, allowing Templar Assassin to be damaged.
* 
Static Link empties Templar Assassin's damage output even with the bonus from Refraction, and will keep doing that even if the Razor cannot see her during Meld.
* Plasma Field can easily strike her during Meld.
Templar Assassin
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna, Doom
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna, Doom
Naga Siren
* 
Lion may upgrade 
Mana Drain, 
Hex and 
Finger of Death through Talent Tree and Aghanim's itens to make them affect secondary targets or turn them into AoE abilities. This can make things difficult for heroes like Phantom Lancer, Naga Siren and Terrorblade, who rely on illusion armies.
Additional:
* Both Hex and Mana Drain destroy Naga Siren's illusions in an instant, making it hard for her to teamfight or push against a team with Lion. If Lion chooses the AoE effect talent for Hex or the shard for multi-target Mana Drain, it can negate her pushing potential entirely.
* 
Earth Spike is an AoE disable with good damage. If used well, it can help distinguish the true Naga Siren by the damage they take (illusions take more damage).
Templar Assassin
* Heroes who can provide True Sight are always credible threats: 
Slardar, Bounty Hunter, especially Zeus since his 
Lightning Bolt provides True Sight without the need to detect her beforehand to apply the debuff. So even a late-coming Zeus can easily scout a large area to reveal her, and she cannot purge herself from his sight with the dispel talent.
Naga Siren
* Zeus's abilities deal high amounts of burst magical damage, which ignores Naga Siren's high armor.
* Arc Lightning is a good way to destroy Naga Siren's illusions due to it's capabilities to bounce between enemies.
* 
Static Field from Aghanim's Shard can automatically hit everything in a big radius, taking a huge chunk of health out of Naga Siren's illusions, regardless of how much health they have.
Templar Assassin
* Although Lightning Bolt and 
Thundergod's Wrath can reveal Templar Assassin during Meld, Zeus nonetheless has no way to deal with Refraction.
* Zeus is a rather squishy hero, falling easily to Templar Assassin's high burst damage.
Additional:
* Refraction blocks all of Zeus' damage and Zeus has no innate way of removing the instances quickly.
* Meld helps burst down Zeus' small health pool while he's still working through the Refraction instances.
* Psi Blades allow her to harass and zone Zeus in lane.
* Templar Assassin usually buys Blink Dagger, enabling her to quickly close the gap to Zeus' defensive positioning.
Templar Assassin
* Because Templar Assassin does not have escape potential in lane, any support hero with roaming potential and a Dust of Appearance can be great at shutting her down early game: Earth Spirit, Spirit Breaker, Tusk, Bounty Hunter, Riki, Warlock.
Templar Assassin
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna, Doom
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna, Doom
Naga Siren
* Medusa's 
Split Shot and 
Mystic Snake combined with Mjollnir, a common item for Medusa, will whittle down all of Naga Siren's illusions, including Naga Siren herself.
* Medusa's Stone Gaze can disable Naga Siren even for the duration of Song of the Siren and even if Naga Siren is spell immune, discouraging Naga Siren from even trying to use Song of the Siren to save herself or counter-initiate against Medusa.
Additional:
* Medusa's Split Shot and Mystic Snake combined with Mjollnir, a common item for Medusa, will whittle down all of Naga Siren's illusions, including Naga Siren herself.
* Medusa's Stone Gaze can disable Naga Siren even for the duration of Song of the Siren and even if Naga Siren is spell immune, discouraging Naga Siren from even trying to use Song of the Siren to save herself or counter-initiate against Medusa.
Naga Siren
* Heroes that build Diffusal Blade or can fit it well into their item build will also make Medusa much less tanky: Riki, Naga Siren, Terrorblade, 
Juggernaut, 
Spectre, Slark.
Templar Assassin
* 
Track provides vision on Templar Assassin during her Meld, allowing him and his teammates to gank her often until she buys a Black King Bar or the {ValueColor:1|Meld Dispels|20tal} {Symbol:Talent} talent to dispel it.
Additional:
* Track provides vision on Templar Assassin during her Meld, allowing him and his teammates to gank her often until she buys a Black King Bar or the {ValueColor:1|Meld Dispels|20tal} {Symbol:Talent} talent to dispel it.
Naga Siren
* Naga Siren with Mirror Image
* Heroes that can remove the Track debuff with their skills:
* 
Abaddon with 
Aphotic Shield and 
Borrowed Time
* 
Huskar with 
Life Break
* Juggernaut with Blade Fury
* 
Legion Commander with 
Press the Attack
* Lifestealer with 
Rage and 
Infest
* Naga Siren with Mirror Image
* 
Omniknight with 
Heavenly Grace
* Oracle with Fortune's End and 
False Promise
* Phantom Lancer with 
Doppelganger
* Slark with 
Dark Pact
* Ursa with 
Enrage
* Weaver with 
Time Lapse
* 
Tidehunter with 
Kraken Shell when damage received reaches the threshold.
Additional:
* Bounty Hunter is a single target damage dealer, so he will not fare well against Naga Siren. Even though Bounty Hunter can use Track on her, Mirror Image will dispel the effect. Ensnare also reveals invisible units while they're rooted, putting Bounty Hunter at a disadvantage.
Templar Assassin
* Dark Pact rips through Refraction charges and still steals attributes during Refraction.
* Pounce and Dark Pact will still hit Templar Assassin while she is Melded. Since she cannot move, both abilities will be easy for Slark to land.
Naga Siren
* Ensnare prevents using any kind of movement abiilties, Making Naga Siren good against heroes who rely on gap-closing abilities to escape: Phantom Assassin, Magnus, Slark, Riki, 
Faceless Void, 
Storm Spirit.
Naga Siren
* Luna's 
Moon Glaives and 
Lunar Blessing can clear waves of Naga Siren's illusions from Mirror Image.
* Once Naga Siren's illusions are cleared with Aghanim's Shard upgraded Moon Glaives, Eclipse can often finish off Naga Siren before she can escape with Song of the Siren.
* A well-timed Aghanim's Scepter upgraded Eclipse combined with 0.25 Eclipse Lucent Ministun talent can be casted at long range and allow Luna to burst down Naga Siren faster and repetively stun Naga Siren, preventing her from escaping with Song of the Siren and 
Town Portal Scroll without getting caught in it's range.
* Luna is a natural Black King Bar wielder unlike Naga Siren who barely goes for it, which allows Luna to freely attack Naga Siren during Song of the Siren and potentially get rid of the most of the damage and crowd-control from Naga Siren.
Additional:
* Luna's Moon Glaives and Lunar Blessing can clear waves of Naga Siren's illusions from Mirror Image, especially when combined with 
Gleipnir and Manta Style. Aghanim's Shard upgraded Moon Glaives can also be used to destroy Naga Siren's illusions and damage the real Naga Siren if they are too close to Luna while also reducing any damage Naga Siren inflicts on Luna for their duration.
* Once Naga Siren's illusions are cleared, Eclipse can often finish off Naga Siren before she can escape with Song of the Siren.
* A well-timed Aghanim's Scepter upgraded Eclipse combined with 0.25 Eclipse Lucent Ministun talent can be casted at long range and allow Luna to burst down Naga Siren faster and repetively stun Naga Siren, preventing her from escaping with Song of the Siren and Town Portal Scroll without getting caught in it's range.
* Luna is a natural Black King Bar wielder unlike Naga Siren who barely goes for it, which allows Luna to freely attack Naga Siren during Song of the Siren and potentially get rid of the most of the damage and crowd-control from Naga Siren.
Naga Siren
* Heroes that create illusions: Spectre, 
Shadow Demon, Phantom Lancer, Naga Siren, Chaos Knight, Terrorblade) or bring other units into the fight (such as Nature's Prophet, 
Lone Druid, 
Chen, 
Enchantress, Meepo and 
Arc Warden) can cause Eclipse to strike the illusions/summons unintentionally. However, in many cases Moon Glaives can resolve this issue and eliminate them before activating Eclipse, but that will require lots of farming for right-click items.
Templar Assassin
* Swashbuckle quickly burns away Refraction charges.
* Lucky Shot can possibly disrupt Templar Assassin when she is boosted with Refraction.
* Pangolier's abilities which does not need to target and has big area of effect allows him to damage her even during Meld.
* Pangolier's high mobility easily shrug off the slow from Psionic Trap.
Naga Siren
* Heroes who are illusion based, or even heroes who frequently build Manta Style can be cleared quickly by Pangolier's high damage, or lose their damage ouput because of Lucky Shot: Chaos Knight, Naga Siren
Templar Assassin
* Powerful physical hitters that can destroy Pangolier during his rolling from afar: 
Drow Ranger, 
Sniper, Templar Assassin, Arc Warden
Naga Siren
* Heroes with powerful rooting abilities will disable most of Pangolier's skills, a bonus point if it pierces spell immunity since it will also be able to stop Pangolier during his Rolling Thunder: Treant Protector, Meepo, Crystal Maiden, Dark Willow, Underlord, Naga Siren
Templar Assassin
* Venomancer's entire arsenal deals lingering damage over a long time and therefore burns through her Refraction very quickly. Not only that, his persistent slow from 
Poison Sting (it can be re-applied again and again with 
Plague Ward) allows his team to catch up to her even with the disruption from her Psionic Trap.
Additional:
* Venomous Gale and Plague Wards allow to quickly melt through Refraction charges.
* Both Poison Nova and Venomous Gale hit invisible units, so Meld cannot be used defensively.
Templar Assassin
* Slardar can attack through Plague Wards and gain 
Bash of the Deep charges, and Templar Assassin can spill Psi Blades through Plague Wards too.
Templar Assassin
* Refraction can be very useful in safely neutralizing Proximity Mine fields, or absorbing Techies' Blast Off combo.
Naga Siren
* Heroes with summons like Broodmother, Enigma, Nature's Prophet; or illusions, like Naga Siren, Terrorblade are effective at keeping the choke points and rune spawns safe from Proximity Mines.
Templar Assassin
* Heroes who can delivers a big chunk of damage in few hits will find themselves struggle against Templar Assassin's Refraction: Sven, Phantom Assassin, Ursa, Wraith King, Lifestealer
Naga Siren
* Ensnare prevents using any kind of movement abiilties, Making Naga Siren good against heroes who rely on gap-closing abilities to escape: Phantom Assassin, Magnus, Slark, Riki, Faceless Void, Storm Spirit.
Templar Assassin
* Heroes who can delivers a big chunk of damage in few hits will find themselves struggle against Templar Assassin's Refraction: Sven, Phantom Assassin, Ursa, Wraith King, Lifestealer
Naga Siren
* Heroes with illusions: Chaos Knight, Naga Siren, Phantom Lancer, Terrorblade
Templar Assassin
* Heroes who can delivers a big chunk of damage in few hits will find themselves struggle against Templar Assassin's Refraction: Sven, Phantom Assassin, Ursa, Wraith King, Lifestealer
Naga Siren
* Heroes with summons and illusions such as Broodmother and Naga Siren, are ill-suited for Wraith King to fight, as he has no source of waveclear.
Naga Siren
* Naga Siren can make landing Chen's combo very hard due to her being an illusion hero thanks to Mirror Image.
* Rip Tide can deal big damage to Chen and reduce Chen's armor, as well as easily kill all of Chen's creeps.
* Naga Siren often builds 
Radiance, which allows her to quickly clear Chen's creeps.
* Ensnare will prevent Chen from escaping.
* With Aghanim's Scepter, Naga Siren can get access to Reel In, which can separate Chen from his creeps and draw him closer to Naga Siren and her team to finish her off. To make things worse, Chen has no way to cancel Reel In on his own, and must rely on outside from {U:Centaur Conqueror} or {U:Mud Golem} under his control.
* Carry or Nuker Naga Siren can often finish off Support Chen before he can have a chance to activate 
Hand of God.
Additional:
* Naga Siren can make landing Chen's combo very hard due to her being an illusion hero.
* Rip Tide can deal big damage to Chen and reduce Chen's armor, as well as easily kill all of Chen's creeps.
* Naga Siren often builds Radiance, which allows her to quickly clear Chen's creeps.
* Ensnare will prevent Chen from escaping.
* With Aghanim's Scepter, Naga Siren can get access to Reel In, which can separate Chen from his creeps and draw him closer to Naga Siren and her team to finish her off. To make things worse, Chen has no way to cancel Reel In on his own, and must rely on outside from {U:Centaur Conqueror} or {U:Mud Golem} under his control.
* Carry or Nuker Naga Siren can often finish off Support Chen before he can have a chance to activate Hand of God.
Templar Assassin
* Templar Assassin can easily counter Invoker's last hitting process in the early game with Refraction. Refraction also negates the stun from Cold Snap, since it will need to deal damage in order to apply its stun.
* Additionally, Refraction completely blocks damage from Sun Strike should Invoker try to finish her off, provided she activate Refraction beforehand.
Naga Siren
* Naga Siren is a natural split-pusher. With Rip Tide, she will easily out-push Nature's Prophet, farming his treants in the process.
* Ensnare prevents 
Teleportation. Even if he hides inside 
Sprout, Song of the Siren lasts long enough to prevent him from escaping.
Additional:
* Naga Siren is a natural split-pusher. With a Radiance equipped, she will easily keep the lanes pushed out, therefore keeping backdoor protection enabled and preventing Nature's Prophet from dealing building damage.
* Ensnare can prevent Teleportation. Aghanim's Scepter upgraded Ensnare can also affect Nature's Prophet even if he is spell immune. And Reel In from Aghanim's Scepter can also be used to separate Nature's Prophet from his treant and bring him close to Naga Siren and her team to burst him down.
* Song of the Siren will stop Nature's Prophet from escaping even if he has hidden inside of Sprout. Aghanim's Shard upgraded Song of the Siren can also heal her allies and save them from Nature's Prophet.
Templar Assassin
* Refraction protects against Anti-Mage's low burst damage, and allows her to win most fights against Anti-Mage during the early game.
* Meld's burst damage and armor reduction is often enough to finish off Anti-Mage before he Blinks away.
Naga Siren
* Song of the Siren is very difficult for Rubick to 
Spell Steal when he is affected by sleep.
* Ensnare and Rip Tide together with some attacks can take Rubick down quickly, due to his low health pool and armor.
* Naga Siren usually buys Diffusal Blade, which may prevent Rubick from using his abilities.
* Mirror Image allows Naga Siren to dodge the incoming stun from 
Telekinesis (when she is not a target), and it can also dispel 
Fade Bolt's damage reduction debuff.
Templar Assassin
* Shadow Fiend's fragility and lack of a natural escape mechanism makes him a great target for Templar Assassin's Meld.
* Shadow Fiend's burst damage, such as 
Shadowraze and Requiem of Souls, is easily nullified by her Refraction.
Naga Siren
* Ensnare and Song of the Siren can be used to cancel both, 
Tether and 
Relocate and to close the distance on Io.
* Rip Tide combined with illusions from Mirror Image often finish off Io before he can save himself with Tether or Relocate.
* 
Spirits's weak area-of-effect makes it a bad tool to deal with Naga Siren's illusions from Mirror Image.
* Once Naga Siren buys Aghanim's Scepter, she can gain access to Reel In, which not only allows her to cancel both, Tether and Relocate, but also to pull Io to herself and her team while he is affected with Ensnare, similarly to Batrider's Flaming Lasso.
* Aghanim's Shard upgraded Song of the Siren can also heal the hero Io and his Tethered targed try to gank.
Additional:
* Ensnare and Song of the Siren can be used to cancel both, Tether and Relocate and to close the distance on Io.
* Rip Tide combined with illusions from Mirror Image often finish off Io before he can save himself.
* Spirit's weak area-of-effect makes it a bad tool to deal with Naga Siren's illusions from Mirror Image.
* Once Naga Siren buys Aghanim's Scepter, she can gain access to Reel In, which not only allows her to cancel both, Tether and Relocate, but also to pull Io to herself and her team while he is affected with Ensnare, similarly to Batrider's Flaming Lasso.
* Aghanim's Shard upgraded Song of the Siren can also heal the hero Io and his tethered targed try to gank.
Templar Assassin
* Refraction negates all of Void Spirit's burst damage.
* Meld quickly burns through 
Resonant Pulse.
Templar Assassin
* Templar Assassin easily withstands all the damage from Skyrwrath Mage, thanks to its first ability Refraction. In addition, Templar Assassin can kill Skywrath Mage with a single hit from under the second ability Meld.
Additional:
* Templar Assassin easily withstands all the damage from Skyrwrath Mage, thanks to its first ability Refraction. In addition, Templar Assassin can kill Skywrath Mage with a single hit from under the second ability Meld.
Naga Siren
* Mirror Image can be effective since Night Stalker cannot withstand fighting illusions. If he's unable to tell which Naga Siren is real, he will have a hard time landing his 
Void. However, if Night Stalker obtains an Aghanim's Scepter, the upgraded Void will hit and may even locate the real Naga Siren in fights.
Additional:
* Ensnare and Song of the Siren prevents Night Stalker from escaping and ganking during daytime or even nighttime.
* Rip Tide reduces Night Stalker's armor, making him easier to focus down.
* Mirror Image can be effective against Night Stalker, due to his single target abilities.
Naga Siren
* Even though Naga Siren relies on direct attacks to deal damage for most of the time, Song of the Siren allows her to easily waste 
Guardian Angel.
* Ensnare fully works on targets affected with Heavenly Grace. However, Ensnare is dispellable with any dispel, and so can be dispelled by Heavenly Grace.
* As an agility hero that relies on illusions, Naga Siren is one of the most natural Diffusal Blade carriers, the bane of every hero with a small mana pool. Naga Siren can also buy items that deal magical damage like Radiance, 
Dagon, 
Ethereal Blade, 
Revenant's Brooch, 
Veil of Discord and Gleipnir to attack Omniknight's allies protected with Guardian Angel.
Additional:
* Although Naga Siren relies mostly on physical damage, Song of the Siren can be used to time out Guardian Angel, giving Naga Siren's team an easy opportunity to counter-initiate.
* Radiance allows it's owner to deal magical damage to multiple enemy heroes at once, and since Naga Siren often buys it, Guardian Angel is not a very good ability for protection against Naga Siren.
* Likewise, Nuker build Naga Siren (which primarly consists of items such as Radiance, Ethereal Blade, Dagon and Veil of Discord) can render Guardian Angel useless. Although Nuker is not a role Naga Siren should be playing.
Naga Siren
* Song of the Siren completely wastes Abaddon Borrowed Time while keeping him in place.
* Naga Siren is able to simply dispel Abaddon's 
Curse of Avernus with Mirror Image before getting hit 4 times consecutively.
* Although Naga Siren's illusions can be easily destroyed by Aphotic Shield, Naga Siren can resolve that issue easily by purchasing 
Heart of Tarrasque to drastically increase her durability. Plus, the said item makes Naga Siren harder to be distinguished from her illusions.
Templar Assassin
* Terrorblade's high armor makes him exceptionally tanky against physical attacks, and Templar Assassin's main damage source is mostly physical damage, it would be difficult for her to take down Terrorblade quickly even with Meld and Refraction.
* Terrorblade's illusions combo with Manta Style and 
Reflection can make a short work to burn Refraction instances, and combined with 
Eye of Skadi, Terrorblade can chase down Templar Assassin easily.
* 
Sunder is not blocked by Refraction's damage block.
Templar Assassin
* Heroes whose attacks allow them to deal either magical or pure damage that can bypass Terrorblade's high armor: Faceless Void, Silencer, Spirit Breaker, Spectre, Templar Assassin, 
Outworld Destroyer.
Naga Siren
* Naga Siren can very easily dispel the Reflection with Mirror Image. And Besides Reflection that can be used to detect real Naga Siren, Terrorblade has no other ways to deal with Naga Siren's illusions. And what's worse is that Naga Siren can much easily detect the real Terrorblade due to 
Conjure Image having illusions having different colors. In addition, Terroblade is not a common Battle Fury nor Mjollnir wielder to counter this problem.
* Aghanim's Scepter upgraded Ensnare will allow Naga Siren to root Terrorblade even ithrough Black King Bar. And with Aghanim's Scepter, Naga Siren can get access to 
Reel In ability, which can allow her to pull Terrorblade toward herself and her team and away from his illusions, even through Black King Bar.
* Naga Siren can rapidly damage Terrorrblade and weaken Terrorblade's armor with Rip Tide, which combined with Terrorblade's low health and strength gain can almost completely discourage Terrorblade from even being present in teamfights. Rip Tide can also weaken armor of Terrorblade's illusions and damage them.
* Song of the Siren can be used to save an ally whom Terrorblade has used Sunder under the condition Naga Siren is quick enough to do it. And since Terrorblade has no "real" burst damage potential outside from Sunder, Naga Siren will usually have plenty of time to save an allied hero on which Sunder was used. Aghanim's Shard upgraded Song of the Siren can also heal her allies around her for it's duration, which allows Naga Siren to nullify effects of Sunder.
* However, Naga Siren's lack of burst damage can make it difficult for her to burst down Terrorblade before he can use Sunder unless Naga Siren has either Black King Bar or 
Linken's Sphere to protect herself against it or if she is played as Nuker.
Additional:
* Naga Siren can very easily dispel the Reflection with Mirror Image. And Besides Reflection that can be used to detect real Naga Siren, Terrorblade has no other ways to deal with Naga Siren's illusions. And what's worse is that Naga Siren can much easily detect the real Terrorblade due to Conjure Image having illusions having different colors. In addition, Terroblade is not a common Battle Fury nor Mjollnir wielder to counter this problem.
* Aghanim's Scepter upgraded Ensnare will allow Naga Siren to root Terrorblade even through Black King Bar. And with Aghanim's Scepter, Naga Siren can get access to Reel In ability, which can allow her to pull Terrorblade toward herself and her team and away from his illusions, even through Black King Bar.
* Naga Siren can rapidly damage Terrorrblade and weaken Terrorblade's armor with Rip Tide, which combined with Terrorblade's low health and strength gain can almost completely discourage Terrorblade from even being present in teamfights. Rip Tide can also weaken armor of Terrorblade's illusions and damage them.
* Song of the Siren can be used to save an ally whom Terrorblade has used Sunder under the condition Naga Siren is quick enough to do it. And since Terrorblade has no "real" burst damage potential outside from Sunder, Naga Siren will usually have plenty of time to save an allied hero on which Sunder was used. Aghanim's Shard upgraded Song of the Siren can also heal her allies around her for it's duration, which allows Naga Siren to nullify effects of Sunder.
* However, Naga Siren's lack of burst damage can make it difficult for her to burst down Terrorblade before he can use Sunder unless Naga Siren has either Black King Bar or Linken's Sphere to protect herself against it or if she is played as Nuker.
Templar Assassin
* Sniper destroys Templar Assassin Refraction's only defense with its 
Shrapnel ability, which is why it can easily punch it and kick it off the line, getting more level and gold.
* The huge range of Sniper's attack due to the 
Take Aim ability allows him to spend the whole game at a distance far from Templar Assassin, constantly punching her with his physical attacks, which is why Templar Assassin remains either to run away or hide in Meld, however, even there Sniper will not let her escape with the help of Blink Dagger, since he uses Shrapnel.
Additional:
* Sniper destroys Templar Assassin Refraction's only defense with its Shrapnel ability, which is why it can easily punch it and kick it off the line, getting more level and gold.
* The huge range of Sniper's attack due to the Take Aim ability allows him to spend the whole game at a distance far from Templar Assassin, constantly punching her with his physical attacks, which is why Templar Assassin remains either to run away or hide in Meld, however, even there Sniper will not let her escape with the help of Blink Dagger, since he uses Shrapnel.
Templar Assassin
* Heroes with powerful nuke can waste their precious abilites on her Refraction during a ganking attempt or chaos combat: 
Lich, Lina, Sniper, Outworld Destroyer Zeus
Naga Siren
* Ensnare with her attacks allows Naga Siren to gank Sniper easily.
* Rip Tide removes Sniper's very little armor.
Templar Assassin
* As with other heroes mentioned in this section, Templar Assassin is not a hero that is fully "countered" by Crystal Maiden (the way she is against 
Viper and Jakiro), however, the proper combination and execution Crystal Maiden's spells, stacked with her team, can most certainly spell the end for Templar Assassin. Though as the later the game goes, and fighting her without team is not the best choice.
* Frostbite can quickly eat away Refraction charges, leaving Templar Assassin vulnerable for the rest of her team to kill.
* Freezing Field will still apply damage to Templar Assassin when she is under the effect of Meld, making it an even less viable form of escape until a Blink Dagger is purchased.
* Blink Dagger is also cancelled by all of Crystal Maiden's spells, and the fairly short cooldowns on Frostbite and Crystal Nova make her a great asset to a chase against Templar Assassin.
* This is not to say that Templar Assassin has any difficulty killing off the low armor, low HP pool Crystal Maiden, so fighting her alone is never advised.
Templar Assassin
* Fragile supports with low armor are always a good prey, also her Psionic Trap will wear down most attempts to flee with their built-in disables: Silencer, Crystal Maiden, Warlock, Ancient Apparition, Grimstroke, Witch Doctor
Naga Siren
* Mirror Image can dispel Frostbite. A similar effect can be achieved with Manta Style, a core item on Naga Siren.
* Song of the Siren can stop Freezing Field regardless of any kind of invisibility as well as allow Naga Siren's team to quickly close the gap on Crystal Maiden.
* With Aghanim's Scepter, Naga Siren can get access to Reel In ability, which can allow her to pull Crystal Maiden toward herself and her team and cancel Freezing Field even through Black King Bar.
Additional:
* Mirror Image can dispel Frostbite.
* Song of the Siren can stop Freezing Field regardless of any kind of invisibility as well as allow Naga Siren's team to quickly close the gap on Crystal Maiden.
* Ensnare allows Naga Siren and her team to quickly catch up with Crystal Maiden and kill her.
* With Aghanim's Scepter, Naga Siren can get access to Reel In ability , which can allow her to pull Crystal Maiden toward herself and her team and cancel Freezing Field even through Black King Bar.
Naga Siren
* Ensnare prevents using any kind of movement abiilties, Making Naga Siren good against heroes who rely on gap-closing abilities to escape: Phantom Assassin, Magnus, Slark, Riki, Faceless Void, Storm Spirit.
Naga Siren
* Ensnare prevents using any kind of movement abiilties, Making Naga Siren good against heroes who rely on gap-closing abilities to escape: Phantom Assassin, Magnus, Slark, Riki, Faceless Void, Storm Spirit.
Naga Siren
* Illusions make it difficult for Necrophos to target his Reaper's Scythe correctly, thus giving illusion heroes like Chaos Knight or Naga Siren an edge against Necrophos.
Templar Assassin
* Fragile carries with no reliable escaping mechanism can be bursted down in no time: Sniper, Drow Ranger, Clinkz
Templar Assassin
* Fragile supports with low armor are always a good prey, also her Psionic Trap will wear down most attempts to flee with their built-in disables: Silencer, Crystal Maiden, Warlock, Ancient Apparition, Grimstroke, Witch Doctor
Naga Siren
* Nyx Assassin's skillset is mostly single-targeted, therefore he will have difficulties against heroes with illusions and summons: Naga Siren, Broodmother, Lycan, Visage, Phantom Lancer. And to make things worse, Nyx Asassin is not a common Battle Fury, 
Maelstrom, Mjollnir, Gleipnir or Radiance wielder to counter this problem.
Templar Assassin
* Fragile supports with low armor are always a good prey, also her Psionic Trap will wear down most attempts to flee with their built-in disables: Silencer, Crystal Maiden, Warlock, Ancient Apparition, Grimstroke, Witch Doctor
Naga Siren
* Naga Siren with Mirror Image
* Heroes that can dodge Glimpse:
* Puck with 
Phase Shift
* Riki with 
Tricks of the Trade
* Phantom Lancer with Doppelganger
* Ember Spirit with Sleight of Fist and 
Activate Fire Remnant
* Chaos Knight with 
Phantasm
* Naga Siren with Mirror Image
* Tusk with 
Snowball
* Juggernaut with Omnislash
* 
Brewmaster with 
Primal Split
* Lifestealer with Infest
* Phoenix with Supernova
Naga Siren
* Heroes with illusions and summons can swarm and overwhelm Bane, who has no area abilities to deal with them outside from Aghanim's Shard upgraded 
Brain Sap: Broodmother, Chaos Knight, Naga Siren, Nature's Prophet, Phantom Lancer, Terrorblade, Visage, Warlock, Wraith King.
Templar Assassin
* Fragile carries with no reliable escaping mechanism can be bursted down in no time: Sniper, Drow Ranger, Clinkz
Templar Assassin
* Heroes with powerful nuke can waste their precious abilites on her Refraction during a ganking attempt or chaos combat: Lich, Lina, Sniper, Outworld Destroyer Zeus
Templar Assassin
* Heroes who can delivers a big chunk of damage in few hits will find themselves struggle against Templar Assassin's Refraction: Sven, Phantom Assassin, Ursa, Wraith King, Lifestealer
Additional:
* Templar Assassin usually places Psionic Traps inside the Roshan Pit (and can teleport herself to the traps with an Aghanim's Scepter), preventing Ursa from killing Roshan without getting noticed by the enemy team.
Templar Assassin
* Because Oracle uses few, powerful instances of damage to kill enemies, Templar Assassin's Refraction and Visage's 
Gravekeeper's Cloak can absorb his burst damage.
Naga Siren
* Illusion heroes, such as Naga Siren, Phantom Lancer, Chaos Knight, Terrorblade will become strong against Tinker in the late game. Without Aghanim's Scepter Tinker is forced to defensively disarm heroes with Laser, leaving illusions free to deal physical damage which Tinker's low armor makes highly effective. In addition, Mjollnir or Battle Fury, two common pickups against illusion heroes, don't work well on Tinker at all.
Templar Assassin
* Heroes that have disposable area-targeted spells can force her to undo her Meld: Leshrac, Puck, Tiny, Jakiro,. An experienced Templar Assassin could try to use Refraction before Meld so she can tank through those damage without getting her Blink disabled.
Templar Assassin
* None of Puck's abilities have any damage-over-time components, meaning that Refraction is a valuable form of defense against Puck's lane harassment.
* Psi Blades deals pure damage and spills over instantly. Puck cannot reliably dodge the damage with Phase Shift.
Additional:
* Puck high magical burst is almost completely useless against Refraction. Templar Assassin often buys 
Orchid Malevolence to render Puck useless in teamfights.
Templar Assassin
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna, Doom
Naga Siren
* Lycan is a hero focused entirely on single target physical damage and lacks disables or AoE damage. Due to this, he will have difficulties dealing with illusions or Naga Siren's Ensnare.
Naga Siren
* Heroes with summons and illusions can find themselves easily bested by Lina, like Broodmother, Nature's Prophet, Chen, Terrorblade, Naga Siren, Visage, Wraith King, Lycan, Phantom Lancer, Shadow Shaman.
Templar Assassin
* Templar Assassin can outmatch Lina on the center line thanks to her own Psi Blades, which is why the advantage of Lina's long-range attacks become turned against her.
* Refraction is good defense against Lina's burst damage. But remember that Lina can partially counter this with 
Dragon Slave's damage over time.
Additional:
* Outlanes Lina on the center line thanks to her own Psi Blades, which is why the advantage of Lina's long-range attacks become turned against her
* Closes from Lina's magic attacks with her own Refraction, which is why Lina can't make her combination: Light Strike Array, Dragon Slave, 
Laguna Blade and kill Templar Assassin quickly
Naga Siren
* Heroes who are reliant on illusions: Chaos Knight, Phantom Lancer, Naga Siren.
Additional:
* Centaur's 
Retaliate will harm all attacking enemies, which will allow Centaur Warrunner to see which is the real Naga Siren.
* A well timed 
Hoof Stomp followed by 
Double Edge will clear all Naga's illusions and prevent Naga Siren from escaping with Song of the Siren.
Templar Assassin
* Centaur has nothing to deal with Refraction that will negate all of his burst damage.
* Psionic Traps provide good vision, making for him harder to initiate.
Naga Siren
* Heroes who rely on illusions will see them destroyed easily by Overwhelming Odds: Phantom Lancer, Chaos Knight, Terrorblade, Naga Siren
Naga Siren
* Song of the Siren lasts long enough to prevent a successful 
Duel (but only if Naga wasn't the target).
Naga Siren
* Heroes whose attacks can affect multiple enemies at once will clear Naga Siren's illusions. Such heroes include Sven, Magnus, Dragon Knight, Luna, Medusa, Templar Assassin, Gyrocopter, Muerta.
Templar Assassin
* Sven has no easy way to burn Refraction charges and needs help from teammates to kill TA successfully.
Templar Assassin
* Heroes who just want to farm and avoid Lone Druid early will find it very hard to do so when he starts knocking on towers: Templar Assassin, Phantom Assassin, Ember Spirit, 
Morphling.
Naga Siren
* Unless Lone Druid purchases a Black King Bar for his Spirit Bear, Ensnare will easily kite the Spirit Bear.
* Song of the Siren allows Naga Siren and her team to completely bypass the Spirit Bear and hunt for the Lone Druid himself when starting a fight.
* Lone Druid's lack of innate AoE capabilities mean that Naga Siren's illusions have no problem against him.
Naga Siren
* Heroes whose attacks can affect multiple enemies at once will clear Naga Siren's illusions. Such heroes include Sven, Magnus, Dragon Knight, Luna, Medusa, Templar Assassin, Gyrocopter, Muerta.
Naga Siren
* Any long duration disables that can pierce through both, Pierce The Veil and Black King Bar are devastating against Muerta: Enigma's Black Hole, Dawnbreaker's Solar Guardian, Axe's Berserker's Call, Naga Siren's Aghanim's Scepter upgraded Ensnare and Reel In from Aghanim's Scepter, Jakiro's Aghanim's Scepter upgraded Macropyre, 
Bane's 
Fiend's Grip, 
Pudge's 
Dismember, Batrider's Flaming Lasso, 
Beastmaster's 
Primal Roar, Grimstroke's Soulbind, Medusa's Stone Gaze, Magnus's Reverse Polarity.
Naga Siren
* Heroes who are reliant on illusions or summons: Chaos Knight, Broodmother, Naga Siren.
Templar Assassin
* Fragile supports with low armor are always a good prey, also her Psionic Trap will wear down most attempts to flee with their built-in disables: Silencer, Crystal Maiden, Warlock, Ancient Apparition, Grimstroke, Witch Doctor
Naga Siren
* Heroes whose attacks can affect multiple enemies at once will clear Naga Siren's illusions. Such heroes include Sven, Magnus, Dragon Knight, Luna, Medusa, Templar Assassin, Gyrocopter, Muerta.
Naga Siren
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, 
Rubick, Keeper of the Light, Pugna, 
Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, 
Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Naga Siren
* Dazzle can instantly destroy all of Naga Siren's illusions from Mirror Image with Aghanim's Shard upgraded 
Poison Touch used on her or any of her illusions.
Naga Siren
* Mirror Image's illusions can easily walk straight at Dazzle and attack him, due to Dazzle's lack of reliable AoE nukes or disables.
* Ensnare roots Dazzle or his allies, making it harder to stay in range of Dazzle's saving abilities.
* Song of the Siren can be used to initiate a fight with superior positioning, potentially zoning Dazzle's high-impact spells out of the fight.
Templar Assassin
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna, Doom
Naga Siren
* Illusion-based and multi-unit heroes can take advantage of Chaos Knight's lack of area damage: Naga Siren, Phantom Lancer, Broodmother
Templar Assassin
* Huskar's burn damage from 
Burning Spear is incredibly strong against Templar Assassin as it completely cancels out her Refraction from the burning over time which results in making her very vulnerable to ganks and harassments, and in turn forcing her out of the lane.
Naga Siren
* Mirror Image can cause Huskar to Life Break the wrong target.
* Rip Tide reduces Huskar's already low armor.
* Song of the Siren allows teams to recover from Huskar's initiation, as well as the damage over time from Burning Spears.
Templar Assassin
* Heroes who can provide True Sight are always credible threats: Slardar, Bounty Hunter, especially Zeus since his Lightning Bolt provides True Sight without the need to detect her beforehand to apply the debuff. So even a late-coming Zeus can easily scout a large area to reveal her, and she cannot purge herself from his sight with the dispel talent.
Naga Siren
* Illusion heroes like the aforementioned Phantom Lancer or Naga Siren, or heroes that tend to buy Manta Style, like Luna or Juggernaut, will give Slardar a hard time, as his damage is single-targeted.
Naga Siren
* Keeper of the Light can stall pushes with 
Illuminate. This makes him strong against pushing heroes: Terrorblade Naga siren Nature's Prophet and Anti-Mage
Templar Assassin
* Heroes that can jump and kill him: Meepo, Clinkz, Templar Assassin
Naga Siren
* Timbersaw's innate durability provided by 
Reactive Armor is very hard to deal with as Naga Siren as she mostly relies on sustained damage rather than burst damage unless if she is played as Nuker.
* Timbersaw's high pure damage and low-cooldown area-of-effect nukes which are 
Whirling Death, 
Timber Chain, 
Chakram and 
Flamethrower from Aghanim's Shard can also destroy Naga Siren's illusions very fast.
* Timbersaw is a common 
Lotus Orb wielder which allows him to reflect Ensnare back at Naga SIren.
Templar Assassin
* Templar Assassin Meld`s ability will break Timbersaw's armor, which makes it very easy to break through and not feel his Reactive Armor, which will allow the team to kill Timbersaw quickly, or drive him out of the fight.
* Templar Assassin's Refraction ability gives her the ability to avoid damage from Whirling Death, which will give her the ability to deal Timbersaw more damage than he will deal.
Additional:
* Templar Assassin Meld`s ability will break Timbersaw's armor, which makes it very easy to break through and not feel his Reactive Armor, which will allow the team to kill Timbersaw quickly, or drive him out of the fight.
* Templar Assassin's Refraction ability gives her the ability to avoid damage from Whirling Death, which will give her the ability to deal Timbersaw more damage than he will deal. However, he may easily burn through Refraction with Chakram.
Templar Assassin
* Because Templar Assassin does not have escape potential in lane, any support hero with roaming potential and a Dust of Appearance can be great at shutting her down early game: Earth Spirit, Spirit Breaker, Tusk, Bounty Hunter, Riki, Warlock.
Naga Siren
* Ensnare prevents using any kind of movement abiilties, Making Naga Siren good against heroes who rely on gap-closing abilities to escape: Phantom Assassin, Magnus, Slark, Riki, Faceless Void, Storm Spirit.
Templar Assassin
* The damage over time from Viper's 
Poison Attack and 
Viper Strike rapidly wear down Refraction charges, allowing Templar Assassin to be damaged. Additionally, 
Corrosive Skin causes her attacks to apply damage overtime on her as well.
* 
Nethertoxin is a big threat to Templar Assassin. Her initially low range making it very hard to deal against Nethertoxin in the laning phase. At any stage of the game, a Nethertoxin can always force her to undo her Meld.
Additional:
* All of Viper's abilities quickly burn through Refraction charges.
* Templar Assassin's short range, aside from Psi Blades' spill damage, makes her vulnerable to Poison Attack harassment.
* Templar Assassin usually buys health and armor items for damage. Outside of Black King Bar, Viper will almost always be able to kill her when Refraction is down.
Naga Siren
* Naga Siren can easily disjoint, and dispel Corrosive Skin with Mirror Image.
* Since Viper is mostly a single-target hero, he will not have almost any chance against Naga Siren because she is an illusion based hero.
* Viper has no burst damage, so Naga Siren will have plenty of time to use Aghanim's Shard upgraded Song of the Siren heal her allies before Viper can finish them off.
Naga Siren
* Mirror Image's illusions increase Echo Slam's damage.
Additional:
* Earthshaker's strong AoE abilities can clear Naga Siren's illusions, or at least make it easier to distinguish the real one by the damage they take.
* Echo Slam deals more damage against more enemies, which can be devestating against Naga Siren and her illusions.
Templar Assassin
* Her Psionic Traps will usually disable Earthshaker's Blink Dagger prior to a teamfight, preventing him from initiating.
* Refraction blocks all of Earthshaker's abilities.
Templar Assassin
* Because Templar Assassin does not have escape potential in lane, any support hero with roaming potential and a Dust of Appearance can be great at shutting her down early game: Earth Spirit, Spirit Breaker, Tusk, Bounty Hunter, Riki, Warlock.
Additional:
* Warlock can cast Upheaval when Templar Assassin uses Meld, preventing her from escaping at the right moment.
* Warlock can also send his Warlock Golem near where she used Meld, preventing escape by Blink Dagger due to the Warlock Golem's 
Permanent Immolation.
* Warlock's Golem's Permanent Immolation will burn away Refraction with its damage over time.
Templar Assassin
* Fragile supports with low armor are always a good prey, also her Psionic Trap will wear down most attempts to flee with their built-in disables: Silencer, Crystal Maiden, Warlock, Ancient Apparition, Grimstroke, Witch Doctor
Naga Siren
* 
Arcane Orb allows Outworld Destroyer's attacks to deal pure damage that can bypass Naga Siren's armor, and which can clear her illusions in no time.
* 
Astral Imprisonment can be used to harass Naga Siren by reducing her maximum mana and to prevent Naga Siren from escaping with Song of the Siren. Outworld Destroyer can also use Astral Imprisonment to protect himself from Naga Siren.
* 
Sanity's Eclipse will most likely instantly kill Naga Siren along with her illusions. Even if Naga Siren survives Sanity's Eclipse, it's mana allergy debuff will discourage Naga Siren from using her abilities as the mana allergy will heal Outworld Destroyer if she uses them for it's duration.
Templar Assassin
* Refraction blocks most of the damage dealt with Arcane Orb and Sanity's Eclipse if used correctly, and is difficult for Outworld Destroyer to deal with.
* If Astral Imprisonment is on cooldown, then an Outworld Destroyer slowed by Psionic Trap is an easy kill for Templar Assassin, especially during the laning stage.
Templar Assassin
* Flux removes Refraction charges very quickly, and Arc Warden can hit her freely with his better attack animation, speed and range. If she tries to mute in her creep wave, Spark Wraith can quickly kill the ranged creep, forcing her to stay near the melee creeps, again, allowing for easy right clicks.
* With Tempest Double, Arc Warden can easily output 1000 damage (with the stacking of Flux and Spark Wraith and kill Templar Assassin within seconds. She cannot avoid this combo as Spark Wraith will still hit her in Meld.
* A good Arc Warden can destroy the item timings of a Templar Assassin, and mitigate her impact during the mid-game, when she is the strongest.
* In the late game, if Templar Assassin tries to split push with Aghanim's Scepter, Arc Warden's double can always threaten to kill her if equipped with a 
Bloodthorn and a Blink Dagger , or a 
Hurricane Pike, forcing her to have to use Black King Bar to survive.
* Quick reactions can also protect Arc Warden and his allies from Meld strike with Magnetic Field, and if equipped with a Hurricane Pike, Arc Warden can double force himself away from the attacking Templar Assassin to safety, where after her Black King Bar ends, she can die to Arc Warden's right clicks.
Naga Siren
* Naga Siren's illusions from Mirror Image can depush the lanes pushed by the Tempest Double, relieving the pressure.
* Mirror Image can dispel Flux, and the illusions can stop Flux from working to it's full power.
Additional:
* Song of the Siren stops Arc Warden from acting and allows Naga Siren's team to close in on him, past his 
Magnetic Field.
* Mirror Image dispels 
Flux. The illusions created from it also disable the slow from Flux if Arc Warden casts it after Mirror Image.
* Arc Warden's playstyle heavily favors split-pushing, which Naga Siren can compete against with her illusions.
Templar Assassin
*
Pulse Nova can easily burn Templar Assassin's 
Refraction charges quickly, and can also hit her while she is invisible in 
Meld.
Naga Siren
* All of Leshrac's abilities, especially
Pulse Nova, can easily deal with Naga Siren's illusions.
Aghanim's Scepter gives Leshrac access to 
Nihilism ability, that allows him to turn himself along with Naga Siren and her illusions to turn ethereal. And to make things worse, 
Nihilism can slow Naga Siren and her illusions, make them more vulnerable to magical damage and unable to fight back while Leshrac moves faster and does not take increased magical damage for it's duration.
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