Spectre
* Jakiro's early pushing ability from Liquid Fire makes Jakiro very strong against heroes, that take a long time to get online: 
Morphling, 
Naga Siren, 
Spectre.
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.
Spectre
* 
Poof combined with 
Earthbind can be used to easily lockdown and burst Spectre down.
* As Meepo's playstyle is often to come online early to mid game and take over the whole game, Meepo will often be much further ahead of Spectre in farming.
* Meepo's global map presence allows him to effectively hunt for Spectre and disrupt her farm.
* Spectre has no strong AOE abilities or way to control or lock down Meepo.
Naga Siren
* Naga Siren's Song of the Siren may be useful but Poof will destroy all of her illusions.
Spectre
* 
Dispersion reduces damage based on a percentage, which is very minimal against large amounts of small instances of damage such as Trample. It reduces each tick by about 14 at the maximum level, which is very small.
* 
Desolate is never a threat to Primal Beast due to his large health pool and Uproar is still out-damaging the ability.
* Onslaught can allow Primal Beast to chase Spectre fleeing with 
Spectral Dagger, as both skills phase through trees and terrain.
* Primal Beast can be strong enough to force a farming Spectre to flee with 
Haunt, putting it on a long cooldown and potentially leading her to an ally that can finish her off.
* Primal Beast excels at early aggression, pushing weak carries out of lane and farming areas he wants to control. Overall just not a pleasant matchup for Spectre.
Naga Siren
* Illusion heroes will struggle against Primal Beast's area damage capability, such as 
Chaos Knight, Naga Siren, 
Terrorblade.
Spectre
* 
Hex and 
Mana Drain can be used to immediately destroy Spectre's illusion when she Haunts. A fast fingered Lion can protect himself and a teammate.
* Hex and 
Earth Spike are good lockdown spells to control and kill Spectre, especially if she doesn't buy defensive items like 
Linken's Sphere and Black King Bar.
* 
Finger of Death can be used to burst down Spectre when she is low on life as she has very poor magic resistance.
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).
Spectre
* Juggernaut's 
Healing Ward can help save allied supports when Spectre attempts a Haunt kill.
* Juggernaut has a stronger push potential than Spectre, enabling him to end the game early before Spectre can come online.
* Spectre is often paired with two supports that are often weak against Juggernaut.
* Juggernaut also tends to build a 
Manta Style, which can prevent Desolate from taking effect.
* Juggernaut is invulnerable against Dispersion while using 
Omnislash.
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.
Spectre
* Late game heroes are Sven's favourite kind of opponent, such as 
Anti-Mage, Spectre and 
Shadow Fiend.
Naga Siren
* Heroes who depends on illusions and summons: Naga Siren, 
Arc Warden, 
Broodmother will struggle against Great Cleave.
Spectre
* 
Dark Seer can pull together Spectre's illusions with 
Vacuum, and 
Wall of Replica creates an illusion of Spectre that deals massive damage.
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.
Spectre
* Spectre can't escape with Spectral Dagger under X Marks the Spot.
* Kunkka can dominate Spectre's lane using Tidebringer and gain an advantage.
* Ghostship helps your team soak up damage from Haunt.
Spectre
* Familiars will be able to chase Spectre through the trees when she uses Spectral Dagger, while Visage can keep blasting her with Soul Assumption.
* Desolate will almost never proc because Visage will always have nearby Familiars.
Spectre
* Phantom Lancer has higher mobility and the ability to reset any fights with 
Doppelganger can be a nuisance for spectre to fight against.
* Phantom Lancer is a natural carrier of Diffusal Blade and Manta Style, which is outright nullify Desolate. In fact, Phantom Lancer will always have illusions with him at anytime, thus further exacerbated the problem.
* Although Spectre is largely AoE oriented, unfortunately, they are damage-over-time (DoT) rather than burst AoE damage. Without any effective ways to quickly destroy illusion and reveal the real hero, Spectre has little availability to manfight Phantom Lancer at any points in the game.
* Spectre often relies on Spectral Dagger as a pseudo-mobility skill. With her low mana pool and complete dependence on it to catch enemy team, she will soon find herself unable to do anything significant once her mana pool is completely drained.
* Doppelganger can be used to dispel the slow from Spectral Dagger, thus completely render it useless.
Spectre
* Zeus is good against heroes that juke in trees or up cliffs, like 
Batrider, 
Monkey King, Spectre, and 
Tinker, by providing vision in any area with Lightning Bolt, or guaranteeing vision on enemies with Thundergod's Wrath.
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.
Spectre
* Zeus can deal a huge amount of damage, but he lacks defensive abilities, such as good mobility or resistance. Due to that, he doesn't like to be touched by any means. Heroes with higher damage output and good mobility will often get easily near Zeus and trade damage (eventually causing Zeus's downfall). Such Heroes include: 
Lycan, 
Slark, 
Storm Spirit, Spectre and others.
Additional:
* Zeus burst damage can be reduced by Dispersion and reflect some of the damage back to Zeus himself.
* Zeus has low mobility and stays in backlines, Spectral Dagger or Haunt can easily catch him as he has no escape mechanism.
* Since Zeus has low HP, Spectral Dagger and Desolate will quickly tear Zeus down when he's alone.
Naga Siren
* 
Arcane Orb deals pure damage that can bypass Naga Siren's armor, and which can clear her illusions in no time.
* 
Astral Imprisonment can be used 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.
Spectre
* Generally speaking, Spectre is a strong teamfighter but a weak manfighter. She has no tool to deal with troll warlord once he has his sight locked on her.
* Troll often buys 
Silver Edge and 
Monkey King Bar, which greatly countered Spectre's passive and item build (Silver Edge can disable passive while providing some damage, Monkey King Bar provides accuracy to counter 
Radiance and 
Butterfly miss chance).
* Black King Bar allows troll to bypass the damage return from 
Blade mail should Spectre attempts to fight back Troll. However, Black King Bar is generally not very effective against Spectre as her skills can pierce the spell immunity. Still, it offers protection against Blade mail, a common item for Spectre in the mid game.
* Troll has high lifesteal from 
Battle Trance and 
Satanic, which help him survive the damage from Desolate should the break duration is over.
* Battle Trance and 
Fervor mean Spectre will have a hard time fighting troll and cannot take him down, even with equal farm.
Spectre
* Spectre must chase for kills and relies on movement speed for mobility in fights, and has no way to counter the 
Tombstone zombies.
* The potency of 
Soul Rip can be increased from nearby illusions from Haunt.
* 
Decay will shut down Spectre during the laning phase by effectively cutting down her initial health pool.
Additional:
* Spectre must chase for kills and relies on movement speed for mobility in fights, and has no way to counter the Tombstone zombies.
* The potency of Soul Rip can be increased from nearby illusions, so Undying can use Haunt against Spectre.
* Early game Decay will make Spectre easy to shut down in lane.
Spectre
* Venomancer's poison damage-over-time are very effective against Spectre, which is lack of magic resistance from early to mid game.
* Venomancer's multiple slows greatly reduces Spectre's low mobility, even through Spectral Dagger.
* Plague Wards reveals Spectre while she is hiding on trees.
Additional:
* Venomancer's poison damage over time is very effective against Spectre, who tends to lack magic resistance during the early to mid game.
* Venomancer's multiple slows greatly reduces Spectre's movement speed and mobility.
* 
Plague Wards can scout out Spectre while she is hiding in trees.
Naga Siren
* 
Flak Cannon and 
Call Down can easily clear Naga Siren's illusions.
Naga Siren
* 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.
Naga Siren
* Axe will destroy her illusions by proccing 
Counter Helix more often due to him being hit by more attacks.
Spectre
* 
Arctic Burn makes it nearly impossible for Spectre to juke into the trees.
* 
Cold Embrace negates all of Spectre's physical damage. Furthermore, Cold Embrace will generally outheal Desolate.
* 
Winter's Curse can taunt illusions, not only wasting the entire duration of Haunt but also turning its illusions against Spectre's own team.
Spectre
* 
Nether Blast is one of the best tower pushing abilities in the game, with a low cooldown. A competent Pugna will (at the very least) destroy tier 2 towers and make space for his team before Spectre can finally come online.
* Spectre's spells, while not spammable, have a fairly high mana cost, so 
Nether Ward can be fairly damaging to Spectre early game. The mana degen will also dampen Spectre's early game power significantly.
* Once Pugna gets 
Aghanim's Scepter, he can spam 
Life Drain on any illusion Spectre summons, whether it'd be from Haunt, Manta Style, or some other means.
* In addition, Pugna can disable Spectre's Desolate ability (although its damage is pure, it requires physical attacks) with his 
Decrepify ability, leaving Spectre only with Spectral Dagger.
Spectre
* Her illusions with Desolate are very valuable, especially when they are usually paired with Radiance. Unlike blink or force movement, Spectral Dagger's escaping mechanic requires manual movement, and therefore Demonic Purge can hold her back really hard and allow your allies to finish her off.
* If she tries to kill you or any key ally with Haunt at any point of the game, remember to not panic and always use Disruption on the illusion, whether it is fake or the real Spectre herself. When the situation calls, Demonic Purge can save a second victim from a haunting Spectre.
* When upgraded by Aghanim's Scepter, Demonic Purge can remove Spectre from a fight by disabling Desolate and Dispersion, negating her damage and tankiness respectively.
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.
Spectre
* Pudge's Dismember stops Spectre from escaping with Haunt.
* He can easily tank the damage reflected by Dispersion due to his high strength and the healing from Dismember.
* Should Spectre try to get away through the trees or over a cliff with Spectral Dagger, Pudge can hook her back.
* Spectre takes a long time to become powerful, and Pudge can ruin her early game with ganks.
Spectre
* Spectre cannot chase down Anti-Mage with Spectral Dagger because of Blink, though it still grants her team vision over him.
* Counterspell reduces much of the damage from Dispersion and Spectre's Radiance.
* Anti-Mage usually builds a Manta Style, preventing Spectre from dealing any Desolate damage to him once he summons his illusions.
Additional:
* Spectre has no way to prevent 
Blink, for escape or initiation. Anti-Mage can easily pick off enemy supports and Spectre cannot do anything about it.
* 
Mana Break burns through Spectre's low mana pool.
* Manta Style's illusions prevent Desolate's damage.
* Even though Anti-Mage is outcarried by Spectre in the later stages of the game, a competent Anti-Mage with a 
Battle Fury can easily outfarm and get ahead of Spectre before she can come online.
Spectre
* Dispersion will not do anything against throughout the game due to his high lifesteal with Jingu Mastery.
* Monkey King often buys Manta Style, which will deny Desolate benefits in 1v1 situations.
* Haunt will do nothing to stop people trapped within Monkey Kings ultimate.
* In all, Spectre is very easily pressured by Monkey King early into the game and is a very easy gank target to coordinate with your team.
Spectre
* Spectre cannot have a good game if she is pressured heavily in lane, which is something Mars can do. He may even force her to cast Haunt as an escape, putting it on a long cooldown.
* Should Spectre get to the late game, Mars can block a large amount of her damage with Bulwark and can mitigate some of the chaos caused by her Haunt illusions with God's Rebuke.
Spectre
* 
Infernal Blade's damage is calculated by percentage of maximum health, meaning that it will hurt Spectre more than most normal attacks, negating some of her tankiness.
* Doom can pick up several different abilities from neutral creeps using 
Devour, some of which can be annoying to Spectre.
* Mud Golem, Dark Troll Summoner, Harpy Stormcrafter, Satyr Mindstealer or Satyr Tormenter are good examples.
* 
Doom makes Spectre less disruptive. Combined with Aghanim's Scepter, it will disable Spectre passive skills, reducing her potential in teamfights.
Additional:
* Infernal Blade's damage is calculated by percentage of max health. Since Spectre is usually tanky, it will hurt her more than most normal attacks.
* Doom can entirely disable Spectre from a teamfight. If upgraded with Aghanim's Scepter, it will disable her passive skills which is she relies on, crippling her.
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.
Naga Siren
* 
Waveform clear Mirror Image illusion from Naga Siren.
* 
Morph can use morph copy her abilities and combination item Manta Style destroy real Naga Siren's.
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.
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.
Naga Siren
* Timbersaw's innate durability 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 AoE nukes can also destroy Naga Siren's illusions very fast. Timbersaw can also build 
Lotus Orb to reflect 
Ensnare back at Naga SIren.
Spectre
* Heroes with good escapes can usually outmaneuver and escape from Spectre: Slark, 
Clinkz, 
Weaver
Naga Siren
* Heroes with long-lasting, undispellable debuffs will pinpoint the true Naga Siren: 
Spirit Breaker, 
Bloodseeker.
Naga Siren
* Because of his massive AoE damage, Sand King is very effective against illusion heroes: Chaos Knight, Phantom Lancer, Terrorblade, Naga Siren.
Naga Siren
* Heroes who are reliant on illusions or summons: Chaos Knight, Broodmother, Naga Siren.
Naga Siren
* Heroes with long-lasting, undispellable debuffs will pinpoint the true Naga Siren: Spirit Breaker, Bloodseeker.
Spectre
* Void Spirit is strong against heroes who cannot deal with his rotations due to his mobility. Such heroes include Spectre, 
Gyrocopter, Morphling, and 
Chen.
Naga Siren
* Heroes with long cast animations can be continuously interrupted by Battery Assault: 
Centaur Warrunner, 
Jakiro, 
Leshrac, Naga Siren, 
Underlord.
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
Naga Siren
* Cleave heroes will clear her illusions. Such heroes include 
Sven, 
Magnus, 
Dragon Knight in Elder Dragon Form, 
Ember Spirit (via item), 
Phantom Assassin (via talent or item), etc.
Spectre
* Durable heroes relied a lot on their main passive effects and items' effects such as 
Bristleback, Underlord, Spectre and Dragon Knight can be disabled easily with 
Sharpshooter's break, reducing their potential in teamfights.
Naga Siren
* Cleave heroes will clear her illusions. Such heroes include Sven, Magnus, Dragon Knight in Elder Dragon Form, Ember Spirit (via item), Phantom Assassin (via talent or item), etc.
Spectre
* 
Hex can be used immediately to destroy Spectre's illusion when she Haunts.
* Shadow Shaman can use 
Shackles to lock down Spectre for his team.
* Shadow Shaman's 
Mass Serpent Ward and 
Ether Shock help him push lanes and end the game early before Spectre can come online and take over the late game.
Spectre
* Spectre's entire ability set is designed to get to and destroy heroes that stay in the backlines, both carries (like the aforementioned 
Drow Ranger and 
Sniper) and supports (like 
Dazzle and 
Shadow Shaman).
Spectre
* 
Nethertoxin disables Desolate and Dispersion, leaving Spectre with far less damage output and damage mitigation in engagements.
* Spectre is one of the weakest heroes at early levels. Viper can stifle her farm with early fights before Spectre purchases any major items.
Additional:
* Nethertoxin disable passives, negating Spectre's damage and survivability by removing both Dispersion and Desolate.
* Due to Haunt and Radiance's burn, Spectre is heavily susceptible to being persistently slowed and damaged by 
Corrosive Skin without even directly attacking Viper.
* 
Poison Attack and 
Viper Strike further slow Spectre's movement speed to a crawl, while his improved magic resistance means he can easily shrug off Radiance's burn.
Naga Siren
* Illusion or summon-based heroes can be a problem to Viper due to his lack of AoE damage: Naga Siren, Phantom Lancer, 
Beastmaster
Additional:
* 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.
Spectre
* 
Feast deals damage and heals lifestealer based on the target max health. Because Spectre often emphasises on building stat items to increase her HP pool, lifestealer can deal a lot of damage to her and heal himself at the same time.
* 
Ghoul Frenzy slows target, which is bad for Spectre if she does not have Spectral Dagger ready.
* Spectre cannot response to infest if lifestealer choose to stay inside his high mobility allies to approach the backline. 
Rage's bonus movement speed and spell immunity make it even more frustrating.
Naga Siren
* Heroes with illusions: Chaos Knight, Naga Siren, Phantom Lancer, Terrorblade
Spectre
* 
Ball Lightning is the ultimate counter to Spectre's entire toolkit. With this ability, he can score easy kills on Spectre without her having any means of escape early game, kite her and her Haunt illusions when it's later in the game due to her having no form of pseudo-blinks.
* Furthermore, it is very difficult for Spectre to deal any substantial damage against Storm Spirit with Desolate, and without both Manta Style and Diffusal Blade he will always remain on the move.
* Also, Ball Lightning grants invulnerability, and as Storm Spirit likes to spam that ability, he can mitigate the damage done from Dispersion and Radiance.
Additional:
* Storm Spirit can exploit every one of Spectre's weaknesses, and thus is one of the best counters against her.
* Spectre has to be in melee range to deal damage, making her likely to trigger 
Static Remnants and susceptible to being kited by 
Overload procs.
* 
Electric Vortex can lock Spectre down as she doesn't like to build Black King Bar.
* Ball Lightning gives Storm Spirit multiple advantages:
* Spectre cannot evade Storm Spirit, as Ball Lightning is superior to Spectral Dagger in terms of mobility.
* Storm Spirit can kite her and her Haunt illusions when it's later in the game due to her having no form of pseudo-blinks (Reality is far inferior to Ball Lightning).
* It is very difficult for Spectre to deal any substantial damage against Storm Spirit with Desolate. Ball Lightning grants invulnerability and can mitigate damage done from Dispersion and Radiance.
* To mitigate this, Spectre needs a team with hard disable to take Storm Spirit out.
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.
Spectre
* Illusions and summons are double-edge sword type of matchup for Luna. On one hand, they can tank damage from Eclipse, but on the other hand, she can easily clear them before Eclipse with Moon Glaives. Examples include 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).
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, 
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.
* 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.
Spectre
* 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.
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.
Spectre
* Haunt instantly allows her to get up and close with Sniper, and Spectral Dagger makes it difficult to escape from her.
Additional:
* Spectre can reach him easily in the backlines with Spectral Dagger or teleport to him with Haunt.
* He is usually a fair distance away from his allies, so Desolate will quickly tear Sniper down.
* Dispersion reflect or reduce his damage, making her hard to take down even at late game.
Naga Siren
* Ensnare with her attacks allows Naga Siren to gank Sniper easily.
* Rip Tide removes Sniper's very little armor.
Spectre
* 
Shadow Step's low cooldown allows Spectre to teleport to him whenever he decides to push.
* Spectral Dagger allows Spectre to go through Sprout's trees and stun Nature's Prophet if she has a 
Skull Basher or 
Abyssal Blade.
* Spectre loves buying Radiance, which can kill Nature's Prophet's Treants easily.
Additional:
* Spectre can get to him anywhere on the map with Haunt.
* Spectre can pass through his trees with Spectral Dagger.
* Desolate's damage will melt him quickly, as he's alone most of the time.
Naga Siren
* 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.
Additional:
* 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.
Spectre
* Spectral Dagger can severely slow down Chen and allow Spectre to chase him down.
* Spectre often buys Radiance, which allows her to clear waves of Chen's creeps and if Chen has no creeps beside himself, he will suffer serious damage from Desolate.
* Dispersion will make attacks from Chen's creeps only tickle Spectre while also killing themselves in process.
* Haunt can find Chen anywhere on the map, no matter where he is.
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.
Spectre
* Spectre can instantly reveal Bounty Hunter's position on the activation of her ultimate Haunt. She can also semi-reveal( visible but not target-able) Bounty Hunter by hitting him with Spectral Dagger.
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.
Spectre
* Rubick usually positions in the back of a team. Heroes who can sneak up and assault Rubick (e.g. Slark) or damage Rubick from great distance (e.g. Spectre, Sniper) should be treated cautiously, as otherwise the matchup usually ends up badly for Rubick.
Spectre
* None of Spectre's spells are very good for Rubick to 
Spell Steal.
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.
Spectre
* Heroes the make heavy use of illusions, like Chaos Knight, Phantom Lancer, Terrorblade, or Spectre can suffer from Crystal Maiden, as Freezing Field can quickly kill off the entire horde if not stopped.
Spectre
* As Crystal Maiden is squishy with very bad movement speed, Spectre can easily stay on Crystal Maiden with Haunt and Spectral Dagger.
* Late game, with enough farm, Spectre can withstand an entire 
Freezing Field, possibly even causing Crystal Maiden to kill herself from Dispersion.
Naga Siren
* 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.
* 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.
Spectre
* Heroes with global spells that can reach Tinker anywhere on the map: Spectre
Additional:
* His global teleportation with 
Boots of Travel and 
Rearm is easily countered with Haunt, and Spectre can reach him anywhere on the map.
* He is squishy, and if alone Desolate will kill him very fast.
* Dispersion can reflect and reduce 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.
Spectre
* Haunt can ruin Enigma's initiation with 
Blink Dagger, no matter where he is on the map.
* Spectre often buys Radiance, which allows her to deal damage over time to Enigma and put Blink Dagger on cooldown.
* Dispersion reflects the damage of 
Midnight Pulse and 
Black Hole inflicted back to Enigma. This can get even worse for Enigma if Spectre buys Blade Mail.
* All of Spectre's abilities ignore spell immunity, which means that even with Black King Bar, Enigma has absolutely little to no chance against Spectre at any stage of the game.
Naga Siren
* Cleave heroes will clear her illusions. Such heroes include Sven, Magnus, Dragon Knight in Elder Dragon Form, Ember Spirit (via item), Phantom Assassin (via talent or item), etc.
Spectre
* Spectre can use Haunt to intercept and disrupt Magnus's initiation attempts.
* Spectral Dagger can severely slow down Magnus after he uses 
Skewer.
* Magnus often travels alone when he is trying to initiate, so Desolate can be very effective against him.
* In late game, Spectre can survive 
Reverse Polarity initiation thanks to Dispersion.
Additional:
* Spectre disables Magnus' Blink Dagger using her ultimate, and later into the game can usually outlive Reverse Polarity's duration.
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.
Spectre
* Spectre can easily close the distance on Drow Ranger with Haunt and stick on her with Spectral Dagger, effectively disables her 
Marksmanship.
* Spectre does not care if silenced by 
Gust, since Spectre will catch her up regardless.
* Dispersion can reflect some damage back to Drow Ranger should she chooses to attack.
* Be careful once she got her Silver Edge as an attempt to shut you down.
Spectre
* Dispersion can negate Muerta's high attack damage while also dealing lots of return damage back to Muerta, which she is fragile against as she has a small health pool.
* Spectre can use Haunt to quickly engage Muerta and escape her if she uses Pierce the Veil.
* In general, Spectre can out carry Muerta towards the late game with her better survivability, sustained damage, and global presence.
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.
Spectre
* As Ancient Apparition likes to stay far away from the fight to get full effectiveness from 
Ice Blast, he is a very good target for a Haunt gank.
* Ancient Apparition also has no hard disables and escape spells, making him an easy kill for Spectre.
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.
* 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.
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.
* 
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.
Naga Siren
* Cleave heroes will clear her illusions. Such heroes include Sven, Magnus, Dragon Knight in Elder Dragon Form, Ember Spirit (via item), Phantom Assassin (via talent or item), etc.
Spectre
* Dispersion makes it hard for Phantom Assassin to burst down Spectre while also reflecting back Phantom Assassin's high burst damage against herself.
* Black King Bar is useless for Phantom Assassin against Spectre as all of her skills pierce spell immunity.
* Spectre only needs to be careful against 
Fan Of Knives from Aghanim's Shard, as it can disable Desolate and Dispersion, though this issue can be solved by buying Blade Mail, which is a common item on Spectre.
Additional:
* Dispersion makes it hard for Phantom Assassin to burst down Spectre while also reflecting back Phantom Assassin's high burst damage against herself.
* Black King Bar is useless against Spectre as all of her skills pierce spell immunity.
Naga Siren
* Heroes with illusions and summons can be hard for Phantom Assassin to deal with, as she lacks any AoE abilities to deal with them without items: Broodmother, Phantom Lancer, Chaos Knight, Lycan, Naga Siren, Shadow Shaman, 
Visage, Nature's Prophet, Terrorblade, 
Warlock, 
Wraith King.
Naga Siren
* 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.
Additional:
* 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.
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.
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.
Spectre
* Oracle's burst damage is not enough to take down Spectre due to Dispersion.
* Disarm from 
Fate's Edict does not hinder Spectre that much, since she can deal damage even without landing a single attack.
Additional:
* Oracle's burst damage is ineffective against Dispersion.
* Disarm provided by Fate's Edict is not as significant debilitation for Spectre as it might be for other carries since She can do damage even without landing attacks.
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.
Spectre
* If Terrorblade's health gets low enough, Terrorblade's 
Sunder can be used to completely deplete Spectre's health pool without any consequences from Dispersion.
* Terrorblade is one of the few late game heroes that can stand toe to toe and man fight Spectre. Not all is lost if the game goes late when Terrorblade is on your team against Spectre.
Additional:
* If Terrorblade's health is low enough, he can safely use Sunder on Spectre without any consequences from her Dispersion and Spectre has no way to prevent it.
* Although Desolate deals pure damage and can bypass his high armor, Terrorblade usually stays nearby his illusions, effectively disabling Desolate.
* Reflection is effective against her as it does not only slow her down but Desolate can also be used against herself.
* Dispersion damage is reduced thanks to Terrorblade's high natural armor.
* Terrorblade is one of few heroes that can manfight Spectre. Not everything is lost if Spectre managed to reach late game.
Spectre
* Unlike with other heroes who can summon illusions of themselves, Terrorblade's illusions from 
Conjure Image have different colors than other illusions which can be seen even by enemy team, which can also make Terrorblade weak even against heroes he naturally counters: 
Bane, Lifestealer, Spectre, Chaos Knight, Spirit Breaker, Sniper. Terrorblade's only solution to counter this problem is to get Manta Style as quickly as possible.
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 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.
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.
Spectre
* Spectre's entire ability set is designed to get to and destroy heroes that stay in the backlines, both carries (like the aforementioned Drow Ranger and Sniper) and supports (like Dazzle and Shadow Shaman).
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.
Naga Siren
* 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
Additional:
* Ensnare disables Templar Assassin's invisibility and Blink Dagger (a core item on Templar Assassin), and her illusions will break 
Refraction easily.
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
* Heroes with illusions and summons can swarm Bane, who has no area abilities outside from Aghanim's Shard upgraded 
Brain Sap: Broodmother, Chaos Knight, Naga Siren, Nature's Prophet, Phantom Lancer, Terrorblade, Visage, Warlock, Wraith King.
Spectre
* Riki's 
Smoke Screen can make it hard for Spectre to escape or burst down Riki with auto attacks.
* Riki can build Aghanim's Scepter and jump inside an allied carry or offlane tank with 
Tricks of the Trade to do a lot of damage to Spectre while completely avoiding Dispersion.
* Riki is great at destroying supports which are often needed to keep Spectre safe until she comes online. He can take them down quickly in team fights, which will leave Spectre alone against your whole team, a fight that she will most likely not win.
* While on Tricks of the Trade, Riki does not take damage from Dispersion.
Spectre
* Spectral Dagger follows Riki even after he goes invisible and stays on him through Tricks of the Trade, revealing his location.
* Desolate grants Spectre the ability to damage Riki with right clicks regardless of Smoke Screen's blind.
* Riki relies on his high damage to kill is opponents, which is countered by Dispersion.
* Haunt can find Riki globally at any time, negating much of his ganking potential.
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
* 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
* 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.
Naga Siren
* Illusion-based and multi-unit heroes can take advantage of Chaos Knight's lack of area damage: Naga Siren, Phantom Lancer, Broodmother
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.
Spectre
* Spectre can instantly escape Focus Fire or hunt a Windranger with Haunt.
* Spectre can catch up to her with Spectral Dagger, even if she uses Windrun.
* Desolate allows Spectre to hit Windranger through Windrun.
* Dispersion combined with Blade Mail and or 
Vanguard before Vanguard upgrade to Abyssal Blade makes Spectre tanky and or also reflects some damage back to Windranger.
Additional:
* Spectre can catch up to her with Spectral Dagger, even if she uses 
Windrun.
* Spectre can instantly reach a ratting Windranger with Haunt.
* Dispersion can reflect some of her damage, especially from her 
Focus Fire.
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.
Spectre
* Spectral Dagger and Haunt allow Spectre to get close to Lina.
* Desolate is very strong against Lina, who's usually a bit isolated in fights because of her high attack and cast range.
* Dispersion can mitigate a good portion of Lina's burst damage, allowing Spectre to turn on her afterwards.
Additional:
* Spectre can very easily close the distance on Lina with Haunt and Spectral Dagger, and due to Lina's abysmal mobility without a Blink Dagger and terrible health pool and armor, Lina easily gets slaughtered due Desolate.
* Dispersion can mitigate a good portion of Lina's burst damage, allowing Spectre to turn against her afterwards.
Naga Siren
* Sand King and 
Phoenix has many tools to deal with a crowd of Heroes, 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.
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).
Spectre
* Heroes with good escapes can usually outmaneuver and escape from Spectre: Slark, Clinkz, Weaver
Spectre
* Spectre can instantly escape Burning Army or hunt Clinkz with Haunt.
* Spectre can catch up to him with Spectral Dagger, even if he uses Skeleton Walk.
* Desolate allows Spectre to hit Clinkz through Skeleton Walk.
* Dispersion makes Spectre tanky and also reflects some damage back to Clinkz.
Additional:
* Spectre can catch Clinkz with Spectral Dagger, even if he uses 
Skeleton Walk.
* Spectre can instantly reach a ratting Clinkz with Haunt.
* Desolate's damage will melt him quickly, as he's alone most of the time.
Spectre
* Heroes that have a weak laning stage: Spectre, 
Nyx Assassin, 
Clockwerk, Spirit Breaker, Omniknight, 
Pudge.
Naga Siren
* 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.
Additional:
* 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.
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.
Spectre
* 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.
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.
Spectre
* 
Death Pulse can single out Spectre from her illusions, as well as heal his team against her. He also usually stands close to his allies for Death Pulse, effectively disabling Desolate.
Spectre
* Enemies that possess high defenses through magic resistance, damage reduction, or high regeneration will make it difficult to whittle their health down to get to Reaper's Scythe's threshold. Such heroes include Bristleback (although only from behind), Spectre, Ursa, and Dragon Knight.
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.
Spectre
* 
Disruptor can control where she goes with 
Kinetic Field and 
Glimpse. 
Static Storm shuts her down in teamfights.
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
Spectre
* Heroes with good escapes can usually outmaneuver and escape from Spectre: Slark, Clinkz, Weaver
Additional:
* Essence Shift deals 20 extra damage by draining one strength per hit, which cannot be reduced or spread by Dispersion.
* Pounce prevents Spectre from escaping with Spectral Dagger.
* Haunt illusions usually don't deal a lot of damage to Slark as he tends to buy a 
Shadow Blade, preventing Desolate's and Diffusal Blade's damage and activating Shadow Dance's regeneration to make up for any damage caused by Radiance.
* Slark is a natural carrier of Silver Edge, which helps break both Desolate and Dispersion.
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
* 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
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
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.
Spectre
* Spectral Dagger can be used to traverse past Fissure.
* Haunt will usually disable Earthshaker's Blink Dagger prior to a teamfight, preventing him from initiating.
* On the other hand, Haunt will amplify damage done from Echo Slam. Use this to your advantage.
Additional:
* Spectre can use Haunt to intercept and disrupt Earthshaker's initiation attempts.
* Spectral Dagger can be used to traverse past 
Fissure.
* Earthshaker often travels alone when he is trying to initiate, so Desolate can be very effective against him.
* Beware that the Haunt illusions amplify the damage done from Echo Slam, which can prove fatal for Spectre's own team.
Spectre
* Global 
Guardian Angel will protect his allies from Spectre's Haunt, both when they are alone and in teamfights.
* 
Purification is a major problem for melee enemies, Spectre included, since they must be next to an enemy in order to attack. The AoE damage also allows Spectre to be singled out from her illusions.
* 
Degen Aura will prevent Spectre from chasing Omniknight, further exacerbated by her terrible mobility outside Haunt.
Naga Siren
* 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.
Additional:
* 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.
Spectre
* The movement speed granted from 
Shapeshift means that Spectre has no way to punish Lycan if he wants to splitpush or pick off supports. Furthermore, he will kite Haunt and cannot be slowed by Spectral Dagger.
* Lycan is often part of an early game push strategy which is often the best counter to Spectre because she needs a lot of time and space to come online as a late game carry.
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.
Spectre
* 
Slardar's 
Slithereen Crush allows him to stun Spectre and illusions, and 
Corrosive Haze prevents her from juking with Spectral Dagger.
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.
Spectre
* Spectre has no innate disables or silence to stop any of Dawnbreaker's abilities
Desolate's bonus
Dispersion
Desolate's bonus.
Dispersion.
* Solar Guardian allows Dawnbreaker to quickly stand next to one of her allies, denying Spectre any of
* Luminosity outheals the damage dealt by
Additional:
* Spectre has no innate disables or silence to stop any of Dawnbreaker's abilities
* Solar Guardian allows Dawnbreaker to quickly stand next to one of her allies, denying Spectre any of
* Luminosity outheals the damage dealt by
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 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.
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.
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*
Additional:
* Dawnbreaker can easily clear waves of Naga Siren's illusions from
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