Phantom Lancer
* Poof will destroy Phantom Lancer's illusions within a short time.
* Earthbind prevents Phantom Lancer from using 
Doppelganger.
Additional:
* 
Poof from multiple Meepos will destroy illusions quickly.
* 
Earthbind's area root can catch Phantom Lancer in a group of illusions and prevent him from using Doppelganger for a long time.
* Meepo aims to end the game as early as possible, while Phantom Lancer is a lategame hero.
* This also means that, in the late game, Meepo stands no chance against Phantom Lancer.
Legion Commander
* When Legion Commander uses 
Duel on one Meepo, he can use his other Meepos to kill her. If he wasn't dueled, he can help the teammate who was duelled to give the teammate the damage instead of Legion Commander.
* However, if Legion Commander picked up an Aghanim's Scepter and she duels one Meepo, that might be the end of Meepo if Legion managed to gather enough damage from previous duels.
Phantom Lancer
* Phantom Lancer's many illusions increase Echo Slam's damage.
Additional:
* 
Echo Slam deals tremendous damage when multiplied by Phantom Lancer's illusions.
* Earthshaker's AoE abilities can quickly kill Phantom Lancer's illusions.
* 
Enchant Totem with 
Aghanim's Scepter gives Cleave to help destroy illusions.
Legion Commander
* Earthshaker's AoE stuns can save ally against Duel, forcing Legion Commander to spend Aghanim's Scepter or 
Black King Bar.
Phantom Lancer
* 
Plasma Field can destroy Phantom Lancer's illusions or damage them heavily.
* 
Static Link cannot be broken even with Doppelganger, serving as a marker for the real Phantom Lancer.
* 
Storm Surge gives Razor's high mobility to chase down Phantom Lancer making Spirit Lance and 
Diffusal Blade slow useless.
* 
Eye of the Storm along with Aghanim's Scepter can quickly reduce Phantom Lancer's armor.
Additional:
* Plasma Field and Eye of the Storm clears most of Phantom Lancer's illusions.
* Static Link is not dispelled by Doppelganger or 
Manta Style which can be used to mark the real Phantom Lancer while also draining his base damage.
* Razor's high mobility with Storm Surge makes it hard for Phantom Lancer to chase down with 
Phantom Rush. When upgraded with Aghanim's Shard, it makes a quick work of his illusions.
Legion Commander
* Static Link drains Legion Commander's accumulated damage, effectively neutralizing her overall primary advantage, and prevents her from winning Duels.
* Storm Surge's movement speed buff makes Razor and his allies harder to catch and initiate.
* Eye of the Storm, if used beforehand, will always hit Legion Commander during Duels, due to her forced proximity. This drastically lowers her survivability during Duel.
Phantom Lancer
* Swashbuckle,
Maelstrom or Diffusal Blade allow him to quickly destroy Phantom Lancer's illusions.
* Pangolier's high mobility allows him to easily escape from Phantom Lancer, through both Phantom Rush and Diffusal Blade.
* Phantom Rush will cause Phantom Lancer to be stunned by Rolling Thunder, or set himself up for a Shield Crash.
Additional:
* Pangolier's AoE abilities especially 
Shield Crash, are very effective against Phantom Lancer's illusions.
Legion Commander
* 
Lucky Shot can disarm Legion Commander and reduce her armor, which can reduce her chances of winning a duel. If an ally is targeted, Pangolier can simply use 
Swashbuckle to inflict it on her.
* If an enemy Pangolier casts a well-timed 
Rolling Thunder before Legion Commander can cast Duel, it might result in her chasing down Pangolier until his or her ultimate ends, whichever duration ends first, resulting in an open window for enemy allies to target Legion Commander, making her vulnerable and susceptible to any source of attacks. If Legion Commander has an Aghanim's Scepter in her inventory, the risk of wasting a solid 8 seconds would result in a futile duel.
* Dueling Pangolier is normally a mistake, Pangolier can disarm you in the duel, and potentially gain some Duel damage, Only duel Pangolier if at least 1 ally is nearby, and he is on low health, And even then, be wary, A good duel can easily turn against you with one Lucky Shot (Due to Lucky Shot lasting 4 seconds).
Additional:
* Swashbuckle can be used to disarm Legion Commander while she is Dueling an ally, granting her opponent a considerable advantage, Lucky Shot lasts 4 seconds at most wasting Legion Commander's entire Duel, (Or half, if Legion Commander has the Scepter).
* Legion Commander will try not to duel Pangolier alone, as she will almost inevitably lose, thanks to Lucky Shot's disarm, If Legion Commander wants to duel a Pangolier, she must be with atleast a teammate, and if she has her scepter, 3 or 4 teammates.
* Legion Commander is often with her allies, allowing you to rack up some considerable damage resistance with Shield Crash.
Phantom Lancer
* Heroes that require burst damage to kill will be difficult for Phantom Lancer to take down: 
Timbersaw, 
Axe, 
Bristleback, 
Alchemist and 
Underlord
Additional:
* 
Firestorm is very useful for clearing multiple Phantom Lancer's illusions swiftly.
* 
Pit of Malice will continuously disrupt many of Phantom Lancer's illusions, drastically reducing their damage and potency.
* 
Atrophy Aura reduces damage of both Phantom Lancer and his illusions.
* Phantom Lancer has nothing to stop Underlord and his team to escape with Fiend's Gate, nor to intercept them if Undelord chooses to use 
Fiend's Gate to get to the designated points of the map.
Legion Commander
* Atrophy Aura's percentage-based damage reduction greatly diminishes Legion Commander's overall damage output, even if she has won many Duels
* Legion Commander cannot get out the way of Firestorm because she is stationary.
Additional:
* Atrophy Aura makes it hard for Legion Commander to win Duels.
* Fiend's Gate can be used to save Underlord and his allies from a Duel or to intercept Legion Commander, because outside from 
Overwhelming Odds, Legion Commander has no other area-of-effect abilities.
Phantom Lancer
* 
Broodmother, 
Nature's Prophet, 
Phantom Lancer by their nature offer very good target for Splinter Blast and Winter's Curse.
Legion Commander
* 
Cold Embrace saves allies from dying in Duels.
* 
Winter's Curse turns Legion Commander's high damage against her allies, giving the enemy team little time to react.
* However, Winter Wyvern lanes very poorly against Legion Commander due to Press the Attack removing all the debuffs she can give. Winter Wyvern also has little chances of surviving if she gets Dueled herself.
Additional:
* Cold Embrace is very effective against Duel.
* Also, casting Winter's Curse at 
Legion Commander while an ally is in a Duel will stun her for most of the duration, possibly preventing lethal damage dealt to your ally. It can also turn her high-damage against her teammate.
Phantom Lancer
* Phoenix's AoE abilities can prove troublesome for Phantom Lancer.
* 
Fire Spirits dramatically reduces Phantom Lancer and his illusions' attack speed.
* 
Icarus Dive's movement speed reduction makes retreating difficult.
* 
Supernova burns away illusions, and is invulnerable to attacks from illusions.
Legion Commander
* Heroes who can hide the Dueled target (
Outworld Destroyer, 
Shadow Demon, 
Tusk, 
Phoenix with Aghanim's Scepter etc).
Additional:
* Legion Commander relies on her powerful attack and her Duel to be effective. But if Phoenix gets the jump on her first, she can find herself severely slowed, taking heavy damage, and find herself unable to Duel a burning Supernova.
* It must be noted that 
Press the Attack will both dispel the attack slow of Fire Spirits and grant her or whoever she targets bonus attack speed. This allows her to easily destroy a Supernova if caution is not taken to prevent this from occurring. As such, it would be a better decision to simply avoid a farmed or skilled Legion Commander instead of attempting to overpower her.
* If an ally is caught by Duel, Phoenix can use Sun Ray to heal the ally and damage Legion Commander, possibly swinging the Duel in their team's favor. Or with Aghanim's Scepter, Phoenix can save an ally from dying in Duel with Supernova and cancel the Duel as well.
Phantom Lancer
* Heroes with summoned units don't fare well against Dawnbreaker. (Phantom Lancer ,
Beastmaster ,
Lycan).
Legion Commander
* Solar Guardian can save allies who are being dueled and will interrupt her Duel initiation.
Phantom Lancer
* Heroes with global nukes will target and hit Phantom Lancer regardless of his illusions: 
Zeus
Legion Commander
* Heroes with global abilities can give Legion Commander's opponent an edge in Duels from anywhere on the map: Nature's Prophet, 
Ancient Apparition, Zeus, 
Invoker, 
Treant Protector
Legion Commander
* If he isn't broken (break), Abaddon can use Borrowed Time to waste Legion Commander's Duel, As Borrowed Time has a shorter cooldown, Legion Commander can't win duels, effectively reducing her targets by one, Duel also means that Borrowed Time heals Abaddon for the duration of the duel, as Legion can't stop attacking.
Additional:
* 
Aphotic Shield and 
Mist Coil makes it hard for Legion Commander to kill Abaddon's teammates in Duels.
* 
Borrowed Time makes Abaddon nearly impossible to kill in Duels, and often replenishes much of his health because Legion Commander cannot manually stop attacking during Duels.
Legion Commander
* 
Purification prevents Legion Commander from killing her target, and will always hit her during Duels.
* 
Guardian Angel completely wastes Duel's duration and can save an ally across the map when upgraded with Aghanim's Scepter.
Additional:
* Both Guardian Angel and Purification are perfect counters against Duel.
Phantom Lancer
* Phantom Lancer's lack of disables makes it hard for him to stop Echo Stomp's channelling.
* However, due to the long cast time of his abilities, a good Phantom Lancer can use Manta Style and/or Doppelganger to dodge the abilities.
* Phantom Lancer's high agility and relatively low strength make him very vulnerable to Natural Order.
* Additionally, Echo Stomp and Earth Splitter can clear his wave of illusions.
* Should Phantom Lancer tries to increase his health by investing for 
Heart of Tarrasque, Earth Splitter does more damage to him and his illusions.
Phantom Lancer
* Sleight of Fist is the natural counter to Phantom Lancer's army of illusions, especially when combined with 
Battle Fury.
Additional:
* 
Sleight of Fist, allows Ember Spirit to destroy all of Phantom Lancer's illusions.
* 
Flame Guard also deals significant damage to illusions, and protects against Spirit Lance.
* Phantom Rush is unable to catch Ember Spirit when he teleports to his 
Fire Remnants.
Phantom Lancer
* All of Sand King's abilities deal AoE damage.
* However, 
Epicenter is usually a non-issue against Doppelganger.
Phantom Lancer
* His illusions will kill themselves in a few hits because of Retaliate. The nukes from Hoof Stomp and Double-Edge should be enough to clear them for a large portion of the game
* Centaur Warrunner's small mana pool makes Diffusal Blade's damage much lower once Centaur doesn't have any more mana left to burn. Keep in mind that Double Edge does not cost mana.
* Be wary when chasing down Phantom Lancer. Hoof Stomp's terrible cast time makes it quite easy to dodge with Doppelganger.
Additional:
* 
Hoof Stomp and 
Double Edge makes short work of Phantom Lancer's illusions.
* 
Retaliate together with 
Blade Mail reflects Phanton Lancer's damage and quickly destroys his illusions.
Phantom Lancer
* Tidebringer, Torrent and Ghostship destroys Phantom Lancer's illusion army.
* Phantom Lancer can't escape with Doppelganger under your X Marks the Spot, but can use it to dodge it.
Additional:
* 
Tidebringer and Kunkka's AoE abilities in general are effective in clearing Phantom Lancer's illusions.
Phantom Lancer
* Leshrac can easily clear Phantom Lancer's illusions with his huge area of effect damage.
Additional:
* Leshrac's AoE abilities destroy Phantom Lancer's illusions.
* 
Diabolic Edict and 
Pulse Nova require no targeting, thus hitting Phantom Lancer whenever he's nearby.
Legion Commander
* 
Paralyzing Cask can save ally from Legion Commander Duel's until she purchases Aghanim's Scepter.
* 
Voodoo Restoration can heal Witch Doctor allies from Duel's.
* 
Death Ward can help Witch Doctor allies from winning Duel's, if, he is not a target.
Phantom Lancer
* 
Kraken Shell and 
Anchor Smash makes it very difficult for Phantom Lancer's illusions to deal damage to Tidehunter.
* 
Ravage will stun the real Phantom Lancer while clearing most of his illusions.
* Anchor Smash reduces base damage, which is the majority of Phantom Lancer's auto-attack damage.
* An Aghanim's Scepter upgraded 
Gush slows down and reduces all of Phantom Lancer's illusions.
Additional:
* A dozen of Phantom Lancer's illusions with all their might can barely hurt Tidehunter at all thanks to Kraken Shell and Anchor Smash. The only way Phantom Lancer can hurt Tidehunter is through the mana burn provided by Diffusal Blade.
* Even with high chasing power from 
Spirit Lance and Phantom Rush (and even Diffusal Blade), Tide Hunter can shrug it all off with Kraken Shell and escape by using a 
Town Portal Scroll or just moving away.
* The AoE nukes from Ravage, Anchor Smash, and an Aghanim's Scepter-upgraded Gush can clear Phantom Lancer's illusions easily.
Phantom Lancer
* Jakiro's spells inflict AoE damage, meaning he can take down Phantom Lancer's illusion army very quickly.
* Bear in mind, however, that once Phantom Lancer buys Diffusal Blade which can burn Jakiro's mana, Jakiro will be vulnerable to Phantom Lancer 's counter-attacks if he runs out of mana.
Additional:
* Jakiro's AoE abilities are great against Phantom Lancer:
* 
Dual Breath slows down and damages Phantom Lancer and his illusions.
* 
Liquid Fire will not only deal AoE damage but also lowers Phantom Lancer's attack speed.
* 
Ice Path and 
Macropyre combo can easily clear all of Phantom Lancer's illusions.
* Jakiro can predict Doppelganger and Ice Path on top.
Phantom Lancer
* All Timbersaw's abilities deal AoE pure damage and can easily deal with Phantom Lancer's illusions.
* 
Reactive Armor highly negates Phantom Lancer's physical damage, making him having a hard time killing Timbersaw.
Additional:
* Phantom Lancer's lack of burst damage and constant attacks will increase Reactive Armor to max level immediately.
* Coupled with 
Timber Chain, it makes an easy escape and almost impossible for Timbersaw to be killed by Phantom Lancer.
* 
Whirling Death and 
Chakram can instantly destroy large groups of illusions, negating Phantom Lancer's advantage, although Phantom Lancer usually builds Diffusal Blade. It can be a problem in late game.
Phantom Lancer
* Storm Spirit has multiple AoE abilities to deal with Phantom Lancer, especially with Aghanim's Scepter.
* 
Ball Lightning destroys illusions, avoids Spirit Lance, and makes Storm Spirit very hard to catch, even with Phantom Rush.
Additional:
* Ball Lightning with or without the 
Static Remnant talent allows Storm Spirit to destroy Phantom Lancer's illusions quickly. It is also easy to dodge Spirit Lance with Ball Lightning and makes Spirit Storm very hard to catch even with Phantom Rush.
Phantom Lancer
* 
Illusory Orb and 
Waning Rift are effective nukes against Phantom Lancer's illusions, especially in the early game.
* 
Dream Coil limits Phantom Rush and Doppelganger's mobility during teamfights.
Phantom Lancer
* The dragon's splash damage wears down his illusions.
* Early harassment with Breath of Fire hinders his farming.
* Fireball stops his pushes and allows for a defence.
Additional:
* 
Breathe Fire and 
Elder Dragon Form's splash damage takes out Phantom Lancer's illusions quickly.
* If Dragon Knight can 
Dragon Tail the real Phantom Lancer, he and his team can quickly kill him before he has a chance to escape.
Phantom Lancer
* Flak Cannon destroys Phantom Lancer's illusions very quickly.
Additional:
* 
Flak Cannon and 
Call Down destroy Phantom Lancer's illusions very quickly.
Phantom Lancer
* 
Empower helps Magnus' allies clear out illusions.
* 
Reverse Polarity and 
Skewer will pull Phantom Lancer along with his illusions, and reposition them together for easy nuking.
* 
Shockwave deals significant area damage in the early game,destroys phantoms and may even indicate the real Phantom Lancer.
Phantom Lancer
* 
Bushwhack will stun and make a quick work of Phantom Lancer and his illusion when he's near a tree.
* 
Sharpshooter breaks 
Juxtapose and deals hefty damage.
* Sharpshooter ignores Illusions and will only damage and breaks the real phantom lancer, when used right, this will allow you to reveal the real phantom lancer amongst his Illusions
Additional:
* 
Acorn Shot combined with attack modifiers such as Maelstrom or 
Daedalus makes a quick work of Phantom Lancer's illusions.
* Bushwhack will stun Phantom Lancer and his illusions if they're near a tree.
Phantom Lancer
* Heroes who lack burst damage will have a hard time against Mars: Phantom Lancer, Nature's Prophet, 
Lich.
Legion Commander
* Because Duel requires both combatants to face each other, 
Bulwark's effectiveness will be increased by a huge margin, which makes it much more difficult for Legion Commander to win any duels against him.
* 
Spear of Mars and 
God's Rebuke pushes Legion Commander away during Duels against allies.
Additional:
* Bulwark immensely mitigates Duel, even with bonus physical damage, as Bulwark scales by percentage. Mars can also buy time for a dueled ally by pushing Legion Commander away with Spear of Mars.
Legion Commander
* Legion Commander is both good and bad vs Mars, on the plus side she can dispel Spear of Mars with Press the Attack and is a good 
Silver Edge carrier. However, Mars is not an ideal Duel target, as Bulwark will force her to 1: Buy Silver Edge, and 2: Hit Mars with it before the Duel, allowing a skilled Mars to react, especially with 
Eul's Scepter of Divinity. In teamfights, Mars will happily draw attention after using his abilities, and tank the Duel with all spells on cooldown.
Phantom Lancer
* Stroke of Fate's damage increases the more units are hit by it, making it effective against Phantom Lancer's army of illusions.
* Phantom's Embrace and Ink Swell's stun can prevent Phantom Lancer from escaping with Doppelganger if properly timed.
* If he has already used Doppelganger, Soulbind can tie Phantom Lancer to one of his own illusions to keep him in place, or to ensure a kill if Grimstroke's team is unsure which one is the real hero.
Additional:
* 
Stroke of Fate clears Phantom Lancer's illusion easily as it deals bonus damage to more targets.
* 
Ink Swell can be used on an allied hero or Grimstoke himself to stun Phantom Lancer and his illusions.
* 
Soulbind has an undispellable debuff that can be used to mark the real Phantom Lancer. It also prevents him from using Doppelganger.
Phantom Lancer
* 
Dead Shot passes through all of Phantom Lancer's illusions, allowing her to separate him from the illusions easily.
* However, Phantom Lancer's high mobility can still pose a threat to Muerta's limited movement.
Phantom Lancer
* Snapfire's AoE abilities in general are effective in clearing Phantom Lancer's illusions.
Phantom Lancer
* 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.
Additional:
* 
Ion Shell helps taking down illusions quickly, making it easy to identify the real Phantom Lancer.
* 
Surge allows Dark Seer and his teammates to run away from Phantom Lancer, who relies on his Phantom Rush to chase enemies.
Legion Commander
* Enigma can be a perfect counter-initiator with his ultimate. A perfectly timed Black Hole will turn the tide of any initiation, especially from heroes like; 
Spirit Breaker, Legion Commander, Axe, 
Puck, and 
Slardar.
Phantom Lancer
* Shadow Demon's 
Demonic Purge is undispellable.
* Heroes with undispellable debuffs will help identify the real Phantom Lancer through visual effects or debuff indicators, provided that it was cast on the real Phantom Lancer to begin with:
* 
Doom's 
Doom marks Phantom Lancer with a highly visible effect, and also silences and mutes him.
* 
Bloodseeker's 
Rupture shows a clear red trail effect on the real Phantom Lancer.
* Ancient Apparition's 
Ice Blast will only debuff Phantom Lancer and not his illusions.
* 
Grimstroke's Soulbind is undispellable.
* Shadow Demon's Demonic Purge is undispellable.
* 
Monkey King's 
Jingu Mastery is undispellable and puts a big yellow Mark over his head.
Additional:
* Phantom Lancer's strength is the sheer amount of illusions he can conjure, Dissimulate can be cast on an ally that he is focusing to quickly thin out his ranks
* Landing a upgraded Demonic Purge on the real Phantom Lancer prevents him from making very many illusions (His only source being Doppelganger), You can reapply as needed if you have the Shard
* Disrupting Phantom Lancer allows you to create multiple extra illusions with Juxtapose, As he is a common carrier of Diffusal Blade, you can also drain the mana of any nearby heros
Legion Commander
* Heroes who can hide the Dueled target (Outworld Destroyer, Shadow Demon, Tusk, Phoenix with Aghanim's Scepter etc).
Additional:
* Disruption can save allies and mess up an initiation from an enemy Legion Commander. Using Disruption on your ally that is affected by Duel will leave her totally exposed without the benefit of the life steal from 
Moment of Courage. A precise decision to Disrupt Legion Commander or her victim is crucial to waste Duel's potential.
* Demonic Purge cannot be dispelled by a hard dispel from Press the Attack, which in turn can be dispelled by your ultimate.
Phantom Lancer
* Although Phantom Lancer will generate strong illusions, and you can also break his Juxtapose with an Aghanim's Demonic Purge, you have a small chance of guessing which is the real Phantom Lancer after he uses Doppelganger.
Phantom Lancer
* Heroes that require burst damage to kill will be difficult for Phantom Lancer to take down: Timbersaw, Axe, Bristleback, Alchemist and Underlord
Legion Commander
* 
Troll Warlord's melee bash and high attack speed can often help him and his allies win Duels against Legion Commander.
Phantom Lancer
* 
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.
Legion Commander
* Heroes with long or multiple disables will prevent Legion Commander from winning Duels: 
Shadow Shaman, Lion
Legion Commander
* Lion is extremely dependent on his abilities. Silences like 
Silencer's 
Last Word, magic resistance like 
Oracle's 
Fate's Edict, and dispels like Legion Commander's Press the Attack all make his abilities less effective.
Phantom Lancer
* Monkey King's Jingu Mastery is undispellable and puts a big yellow Mark over his head.
* Heroes with undispellable debuffs will help identify the real Phantom Lancer through visual effects or debuff indicators, provided that it was cast on the real Phantom Lancer to begin with:
* Doom's Doom marks Phantom Lancer with a highly visible effect, and also silences and mutes him.
* Bloodseeker's Rupture shows a clear red trail effect on the real Phantom Lancer.
* Ancient Apparition's Ice Blast will only debuff Phantom Lancer and not his illusions.
* Grimstroke's Soulbind is undispellable.
* Shadow Demon's Demonic Purge is undispellable.
* Monkey King's Jingu Mastery is undispellable and puts a big yellow Mark over his head.
Legion Commander
* Heroes that lack burst damage will have a difficult time taking down Monkey King, and fare badly against Jingu Mastery: Legion Commander, 
Lifestealer, 
Weaver, 
Wraith King
Phantom Lancer
* Heroes that can destroy trees will deny Monkey King spots to jump on, or cause him to fall: 
Windranger, Nature's Prophet, Phantom Lancer
Phantom Lancer
* Berserker's Call catches Phantom Lancer when he is hidden among his illusions.
* Counter Helix quickly destroys Phantom Lancer's illusion army. The more illusions there are, the more often Counter Helix is triggered.
* Phantom Lancer's low early game health makes him an easy target for Culling Blade.
Additional:
* 
Berserker's Call helps locking down Phantom Lancer in a group of illusions.
* 
Counter Helix combined with Blade Mail clears Phantom Lancer's illusions quickly.
* Phantom Lancer's low health in the early game makes him a frequent target for 
Culling Blade.
Legion Commander
* Long lockdown is a great way to deal with Axe to prevent Berserker's Call from being used, heroes such as Legion Commander, Beastmaster and 
Primal Beast are good examples of this.
Phantom Lancer
* Low-health, normally mobile carries who rely entirely on raw attack damage are vulnerable to Bane's nukes and disables: 
Anti-Mage, 
Clinkz, 
Drow Ranger, 
Faceless Void, 
Gyrocopter, 
Juggernaut, 
Meepo, 
Mirana, Monkey King, 
Morphling, 
Phantom Assassin, Phantom Lancer, 
Riki, 
Shadow Fiend, 
Slark, 
Sniper, Terrorblade, Troll Warlord, Weaver.
Legion Commander
* Bane has powerful single-target abilities that can help his allies win Duels, or at least cripple Legion Commander for the duration.
* Nightmare can waste Duel's entire duration as the dueled units transfer the Nightmare back and forth. This may be prevented if a non-Dueling unit attacks the Nightmared Dueler.
Additional:
* 
Enfeeble, 
Nightmare and 
Fiend's Grip all prevent Legion Commander from winning Duels, especially when Bane has 
Blink Dagger.
Phantom Lancer
* 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.
Legion Commander
* Heroes with strong dispels can dispel Bane's disables from their allies: Oracle, Legion Commander, 
Omniknight.
Legion Commander
* 
Mystic Flare can easily burst down Legion Commander while she is Dueling.
Phantom Lancer
* Skywrath Mage also has a terrible time fighting against anything that isn't a hero. His skills are mostly target-based and he has terrible strength and agility, he can easily be kited or harassed by illusion-based heroes like Chaos Knight and Phantom Lancer, or by Heroes that summon other units like 
Lone Druid, Lycan and Beastmaster.
Phantom Lancer
* 
Astral Step and 
Dissimilate makes a quick work of Phantom Lancer's illusions.
* 
Resonant Pulse helps clear illusions and protects Void Spirit from Phantom Lancer's physical damage and with the Aghanim's Scepter upgrade, it prevents Phantom Lancer from casting his abilities.
* Void's Spirit mobility makes it hard for him to chase down with Phantom Rush.
Legion Commander
* Special mention to Legion Commander, as she can lock down Void Spirit for a long amount of time without worrying too much about being killed by him during the Duel.
Legion Commander
* Invoker's spells will disable and destroy Legion Commander while she's locked in a Duel.
Legion Commander
* Heroes with long lockdowns: Shadow Shaman, Legion Commander.
Legion Commander
* Song of the Siren lasts long enough to prevent a successful Duel (but only if Naga wasn't the target).
Legion Commander
* Heroes who rely on illusions will see them destroyed easily by Overwhelming Odds: Phantom Lancer, Chaos Knight, Terrorblade, Naga Siren
Phantom Lancer
* Ancient Apparition's Ice Blast will only debuff Phantom Lancer and not his illusions.
* Heroes with undispellable debuffs will help identify the real Phantom Lancer through visual effects or debuff indicators, provided that it was cast on the real Phantom Lancer to begin with:
* Doom's Doom marks Phantom Lancer with a highly visible effect, and also silences and mutes him.
* Bloodseeker's Rupture shows a clear red trail effect on the real Phantom Lancer.
* Ancient Apparition's Ice Blast will only debuff Phantom Lancer and not his illusions.
* Grimstroke's Soulbind is undispellable.
* Shadow Demon's Demonic Purge is undispellable.
* Monkey King's Jingu Mastery is undispellable and puts a big yellow Mark over his head.
Legion Commander
* Heroes with global abilities can give Legion Commander's opponent an edge in Duels from anywhere on the map: Nature's Prophet, Ancient Apparition, Zeus, Invoker, Treant Protector
Phantom Lancer
* Phantom Lancer can dispel or escape from Cold Feet with Doppelganger and Phantom Rush, respectively. Phantom Lancer also frequently builds a Manta Style which dispels Cold Feet.
* Ancient Apparition has trouble dealing with Phantom Lancer's illusions due to a lack of Area of Effect damage other than Ice Blast.
* Phantom Lancer tends to build a Diffusal Blade, which greatly amplifies his damage against Ancient Apparition due to Ancient Apparition's high mana pool.
* Ancient Apparition has no escape/mobility mechanisms, making him an easy target for Phantom Lancer at any stage of the game.
Phantom Lancer
* Doppelganger dispels 
Sticky Napalm and 
Flamebreak.
* There are usually way too many illusions for Batrider to lasso the real Phantom Lancer, since the illusions' hitboxes also body block the real Phantom Lancer.
Legion Commander
* Press the Attack dispels Flaming Lasso.
* Batrider is unlikely to win a Duel in any stage of the game.
Phantom Lancer
* Phantom Rush lets Phantom Lancer get close quickly and disable Marksmanship.
* As Phantom Lancer commonly buys Manta Style, he can easily dispel Gust and then chase after Drow Ranger.
* Because Phantom Lancer is a natural Diffusal Blade carrier, he can easily burn Drow Ranger's mana and render her unable to use Frost Arrow and Gust to save herself.
Legion Commander
* Drow Ranger's low mobility and lack of defensive abilities make her an easy gank target in the early to mid-game.
* A Dueling Drow Ranger will lose her precious 
Marksmanship, reduce her damage output significantly, and will more likely lose that Duel.
Phantom Lancer
* Although 
Viper Strike cannot be dispelled by Doppelganger, Viper's lack of mobility and AoE damage makes him an easy target for Phantom Lancer.
* Viper's various slows do not work against Phantom Rush.
* Although Phantom Lancer should be wary due to 
Nethertoxin applying Break.
Additional:
* Phantom Lancer can overwhelm Viper with spawned illusions from Spirit Lance and Doppelganger. In addition, Diffusal Blade, a core item on Phantom Lancer, burns Viper's limited mana pool, reducing his potential poison damage.
* Viper's various slows do not work against Phantom Rush. Additionally, it is almost impossible to keep Lancer inside Nethertoxin's radius in order to disable the passive.
Legion Commander
* Viper's frailty and low mobility make him an enticing Duel target and 
Corrosive Skin doesn't protect him against Legion Commander physical attacks.
* Press the Attack can dispel 
Poison Attack.
* Viper slows can easily negate by Overwhelming Odds movement speed.
Phantom Lancer
* Illusion and heroes with summons are difficult to kill with Chen's single-target offensive spells: Terrorblade, Phantom Lancer, Chaos Knight, Broodmother, Naga Siren, Lycan, Visage, Beastmaster, Warlock, Wraith King. And even though Chen can convert enemy summons with Holy Persuasion, their much greater numbers will often overwhelm Chen and his creeps.
Legion Commander
* Chen's fragility and low mobility make him an enticing Duel target.
* Overwhelming Odds and Moment of Courage can take advantage of converted creeps's numbers.
* With enough damage from Duel stacks, Legion Commander can also often kill any of Chen's unfortunate allies before he can use Hand of God.
Additional:
* Chen's frailty and low mobility make him an enticing Duel target.
* Overwhelming Odds and Moment of Courage can take advantage of converted creeps' numbers.
* With enough damage from Duel stacks, Legion Commander can also often kill any of Chen's unfortunate allies before he can use 
Hand of God.
Phantom Lancer
* Heroes with single-target abilities and low-mobility are all an exceptionally easy targets for Phantom Rush: Terrorblade, Chaos Knight, Wraith King
Additional:
* With no wave clear and mostly focus on dealing single target damage, Terrorblade will be overwhelmed in no time due to Juxtapose. And to make things worse, Terroblade is not a common Battle Fury nor 
Mjollnir wielder to counter this problem.
* 
Reflection can be dispeled instantly with Doppelganger.
* As Phantom Lancer is a natural Diffusal Blade carrier, he can drain Terrorblade's mana, leaving Terrorblade with no chance to use 
Sunder to save himself.
* Besides Reflection that can be used to detect real Phantom Lancer, Terrorblade has no other ways to deal with Phantom Lancer's illusions. And what's worse is that Phantom Lancer can much easily detect the real Terrorblade due to 
Conjure Image having illusions having different colors.
Legion Commander
* Duel's long duration prevents Terrorblade from swapping his health with Sunder.
* Overwhelming Odds deals high damage to Terrorblade's illusions.
Phantom Lancer
* Carry heroes who can close the gap reliably are very problematic: Phantom Lancer, 
Ember Spirit, Phantom Assassin.
Legion Commander
* Sniper's low mobility and lack of defensive abilities make him an easy gank target for the entire game, especially if Blink Dagger is picked up.
Phantom Lancer
* Juxtapose allows Phantom Lancer to overwhelm Chaos Knight due to his single-target abilities.
* Phantom Lancer often builds a Manta Style, which can be used to disjoint Chaos Bolt or dispel Reality Rift.
* Doppelganger can be used to dodge Chaos Bolt.
* Diffusal Blade, another common item on Phantom Lancer, can quickly drain Chaos Knight's low mana pool, leaving him unable to cast spells.
Additional:
* Chaos Knight's single target abilities are difficult to target against Phantom Lancer's illusions.
* Chaos Knight's lack of mobility makes him an easy target for Phantom Lancer to Phantom Rush and drain his already low mana pool.
Legion Commander
* Heroes with strong area damage to destroy Phantasm illusions: Axe, Ember Spirit, Legion Commander, Phoenix
Phantom Lancer
* Any heroes that naturally buy Diffusal Blade like Phantom Lancer or have a mana break talent is a big issue for Pudge because of his low mana pool.
Legion Commander
* Legion Commander can use Press the Attack on an ally to dispel Dismember. The bonus health regeneration also partially counters the damage of Rot
* Duel can be used on Pudge whilst Rot is active, disabling toggling which may result in a lethal health drain that leaves Legion Commander with a successful duel.
Phantom Lancer
* Due to Phantom Rush and Juxtapose being passives and not affected by silence, a Phantom Lancer with a Diffusal Blade can easily kill Silencer.
Legion Commander
* Heroes that can disable or silence Silencer for a long time, such as 
Bane and Legion Commander, can lock down Silencer while their allies put him down.
Phantom Lancer
* 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.
Legion Commander
* Duel's long duration prevents Nyx Assassin escaping from 
Vendetta. With Aghanim's Scepter, she can also bypass 
Spiked Carapace.
Phantom Lancer
* Illusion-based heroes are effective against Omnislash and Juggernaut's single-targeted damage: Naga Siren, Chaos Knight, Terrorblade,Phantom Lancer.
Legion Commander
* Duel pierces spell immunity and forces him to attack Legion Commander, making him unable to use 
Omnislash.
Phantom Lancer
* Ogre Magi has no undispellable AoE damage or disables and has nothing to deal with Phantom Lancer's illusions.
* Doppelganger disjoints and dispels Ignite.
Legion Commander
* Heroes rely on their debuff to control the opponent will have a hard time against Press the Attack: 
Venomancer, 
Earth Spirit, 
Ogre Magi
Phantom Lancer
* Heroes with no AoE abilities will struggle against Phantom Lancer: Phantom Assassin, Broodmother
Legion Commander
* Overwhelming Odds's damage stacks with each enemy unit in its radius. If this hits Broodmother and a large number of spiders it can deal significant amounts of damage.
* Moment of Courage has a high chance to proc if Broodmother and all of her spiders are attacking her.
* Duel can keep Broodmother in place long enough for Legion's team to kill her.
Additional:
* Overwhelming Odds is great at killing many stacked up spiderlings, thus giving Legion Commander a large buff.
* Duel is a reliable way to lock down Broodmother, preventing her from running into the treeline.
Phantom Lancer
* Illusions can be sent out to destroy 
Techies mines.
Legion Commander
* Heroes with low health will die easily during Duels, and can be farmed for damage in the early game: 
Crystal Maiden, Lich, Techies, 
Rubick
Phantom Lancer
* Heroes with illusions can overwhelm Huskar: Phantom Lancer, Anti-Mage, 
Arc Warden, Chaos Knight.
Legion Commander
* Carries that can out damage Huskar will do well against him: Legion Commander, Faceless Void, Troll Warlord, Phantom Assassin.
Additional:
* 
Life Break is almost suicidal when used on Legion Commander, as it invites an instant Duel and Legion Commander herself is a natural Blade Mail carrier.
* Huskar's low survivability and mostly on low health make him particularly vulnerable to Legion Commander's high physical damage.
Phantom Lancer
* Phantom Lancer with Doppelganger
* 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:
* Doppelganger dispels 
Track.
* Bounty Hunter also has no area of effect abilities to help with the illusions.
Legion Commander
* Legion Commander with Press the Attack
* 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.
Phantom Lancer
* Phantom Lancer can effortlessly overwhelm Morphling with a large number of illusions. It becomes even more effective with {Item ID:Diffusal Blade}, which takes away his mana in the process.
* Doppelganger can be used to dodge Adaptive Strike combo and create confusion with two additional illusions.
* 
Eye of Skadi can be bought to slow and negate the health regeneration from Attribute Shift, and a common item for Phantom Lancer.
Phantom Lancer
* 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.
Phantom Lancer
* 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.
Legion Commander
* Duel renders Anti-Mage's escape capabilities with Blink and Counterspell useless. Blade Mail and Moment of Courage work well against Anti-Mage's relatively low health.
* A good initiation from Legion Commander and her team is enough to effortlessly kill Anti-Mage.
Additional:
* 
Counterspell offer no protection against Duel at all.
* Duel locks down Anti-Mage for a long duration, preventing him from escaping with 
Blink. One successful Duel initiation is usually enough for Legion Commander's team to kill Anti-Mage.
Legion Commander
* Heroes with abilities that blind or cause Legion Commander to miss will prevent her from winning Duels: Arc Warden, 
Keeper of the Light, Riki, 
Tinker
Phantom Lancer
* Heroes with dispels: Legion Commander, Oracle, Slark, Phantom Lancer
Legion Commander
* Press the Attack can dispel Blinding Light or Solar Bind from a hero.
* Duel can be used to instantly take Keeper of the Light out of a team-fight.
Phantom Lancer
* Diffusal Blade is a core item on Phantom Lancer. And when combined with his numerous illusions, it allows him to rapidly deplete Necrophos's mana, rendering Necrophos incapable of doing anything.
* It can be difficult to single out the true Phantom Lancer among his army, giving Necrophos a hard time with aiming his ultimate.
* Even if his illusions are defeated, Phantom Lancer can simply create more of them at his disposal with almost no issues.
Legion Commander
* Duels prevents Queen of Pain from using Blink, which may force her to purchase a 
Linken's Sphere
* Because Queen of Pain is also not a right-click hero, Legion won't have much difficulties in duels.
* Press the Attack dispels Shadow Strike's debuff.
Phantom Lancer
* Slark has no sustained AoE to fight off Phantom Lancer's illusions as they continually spawn.
* Spirit Lance can give vision of Slark by spawning an illusion, making it harder for him to juke and gain the passive bonus from 
Shadow Dance.
* Phantom Rush helps Phantom Lancer chase down Slark if he tries to escape with 
Pounce.
Additional:
* Slark has no sustained AoE damage to deal with a lot of Phantom Lancer's illusions.
* Doppelganger lets Phantom Lancer dodge Dark Pact and Pounce and partially wastes the duration of Shadow Dance.
* Spirit Lance can give vision of Slark via spawning an illusion, making it harder for him to juke and gain the passive bonus from Shadow Dance.
* Phantom Rush helps Phantom Lancer chase down Slark when he jumps away with Pounce.
Phantom Lancer
* Doppelganger is a very reliable tool against Glimpse, enabling him to dodge it consistently.
* Doppelganger also allows Phantom Lancer to escape from Kinetic Field so long as there isn't a Static Storm on top of him.
Additional:
* Doppelganger lets Phantom Lancer instantly escape from 
Kinetic Field.
* Doppelganger is one of the most reliable ways to dodge 
Glimpse, other than spell immunity.
* Doppelganger dispels 
Thunder Strike.
* However, even with the negation of the rest of his kit, 
Static Storm (especially when upgraded with Aghanim's Scepter) remains as one of the strongest lockdowns against Phantom Lancer, and as such Disruptor must never be underestimated.
Legion Commander
* Duel's long duration prevents Weaver from activating Time Lapse or escaping with 
Shukuchi.
Legion Commander
* Duel is a great initiation to kill Death Prophet before she can cast Exorcism. Furthermore, Legion Commander often builds Blade Mail and can reflect Exorcism's damage to kill Death Prophet easily.
Legion Commander
* 
Searing Arrows and Clinkz physical damage items are almost suicidal when used on Legion Commander, as it invites an instant Duel and Legion Commander herself is a natural Blade Mail carrier.
* Duel locks down Clinkz for a long duration, preventing him from escaping with 
Skeleton Walk.
Phantom Lancer
* Phantom Lancer's many illusions will easily destroy 
Tombstone, provided he has sufficient farm.
* He also has no ways of dealing with the illusions, since Decay doesn't steal strength from illusions.
Phantom Lancer
* Lifestealer will struggle to deal with Phantom Lancer's illusions and will either be forced to use his abilities too quickly, or itemize too heavily for them.
* Phantom Lancer commonly builds Diffusal Blade, which poses a large problem to Lifestealer and his low mana pool, and can shut him down from even casting his abilities.
Additional:
* Aside from his ultimate, Lifestealer has no AoE abilities to deal with Phantom Lancer's illusions, nor does he have the mobility to escape Phantom Rush.
* Doppelganger dispels 
Open Wounds.
* Phantom Lancer usually builds Diffusal Blade, which a problem for a low already mana hero like Lifestealer.
Phantom Lancer
* Vengeful Spirit has no strong AoE nuke or disable against Phantom Lancer's Illusions.
* Phantom Lancer is a natural Diffusal Blade carrier, which reduces Vengeful Spirit's low mana pool very quickly, leaving her defenseless.
* Doppelganger can dodge Vengeful Spirit's abilites.
* Phantom Rush with his illusions can chase Vengeful Spirit efficiently.
Phantom Lancer
* Lone Druid and his Spirit Bear lack mobility, and are easy overwhelmed after being slowed by Diffusal Blade.
* 
Savage Roar is useless since Phantom Lancer can return to fight him again with his Phantom Rush.
Phantom Lancer
* Void's slow is dispelled by Doppelganger or counteracted by Phantom Rush.
* Spirit Lance's and Diffusal Blade's slow reduces Night Stalker's mobility and helps him or his ally escape if they're inflicted by Void or Crippling Fear.
* Night Stalker has no AoE abilites to take out Phantom Lancer's illusions. Even if Night Stalker gets an Aghanim's Scepter, there will be way too many illusions for Night Stalker to handle.
Legion Commander
* Heroes rely on their debuff to control the opponent will have a hard time against Press the Attack: Venomancer, Earth Spirit, Ogre Magi
Additional:
* Press the Attack dispels Venomous Gale and Poison Sting from Legion Commander or her teammates.
* Venomancer is an ideal target for Duel due to his lack of mobility and low starting health.
Legion Commander
* Heroes that cannot move in fights such as a Dueling Legion Commander or anyone channeling a spell like Bane, 
Pudge, or 
Enigma are easy Sacred Arrow targets.
Phantom Lancer
* Heroes with summons or illusions makes Sacred Arrow harder to land: Shadow Demon, Phantom Lancer, Nature's Prophet.
Legion Commander
* Heroes that can protect or dispel stunned allies such as Legion Commander, Outworld Destroyer, Shadow Demon and Oracle can reduce the effectiveness of Sacred Arrow.
Legion Commander
* Heroes who rely on summons will see them destroyed easily by Overwhelming Odds: Lycan, Arc Warden, Warlock, 
Chen
Legion Commander
* Heroes with low health will die easily during Duels, and can be farmed for damage in the early game: Crystal Maiden, Lich, Techies, Rubick
Legion Commander
* 
Tethered heroes are much harder for Legion Commander to kill in Duels.
* 
Relocate can cancel Duels and save allies.
Phantom Lancer
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: Beastmaster, Broodmother, Chaos Knight, Lycan, Naga Siren, Nature's Prophet, Phantom Lancer, Shadow Shaman, Terrorblade, Visage, Warlock, Wraith King.
Legion Commander
* Duel is very effective against Io due to its low health and armor.
Phantom Lancer
* 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.
Legion Commander
* Heroes rely on their debuff to control the opponent will have a hard time against Press the Attack: Venomancer, Earth Spirit, Ogre Magi
Legion Commander
* Heroes who rely on summons will see them destroyed easily by Overwhelming Odds: Lycan, Arc Warden, Warlock, Chen
Legion Commander
* Heroes with low health will die easily during Duels, and can be farmed for damage in the early game: Crystal Maiden, Lich, Techies, Rubick
Legion Commander
* Magnetic Field prevents Legion Commander from getting wins with Duel.
Additional:
* 
Magnetic Field prevents Legion Commander from easily gaining wins with Duel.
Phantom Lancer
* Doppelganger dispels Flux.
* Phantom Rush closes the distance between Phantom Lancer and Arc Warden.
* Juxtapose can overwhelm Arc Warden and nullify his kit which is only effective against isolated enemies.
Additional:
* One of Arc Warden's hardest counters, Arc Warden, who has primarily single target damage, will struggle tremendously against Phantom Lancer:
* 
Flux is paused if even one illusion remains near Phantom Lancer. It can also be dispelled with Doppelganger.
* Phantom Lancer can also easily dodge an activated 
Spark Wraith, or use his illusions to trigger it safely.
* Phantom Rush allows Lancer to quickly close gap to get inside of Arc Warden's Magnetic Field.
* Phantom Lancer and his clones are able to quickly drain Arc Warden of his mana with a Diffusal Blade. This means Warden's 
Tempest Double will also be summoned without mana.
Legion Commander
* Heroes who rely on summons will see them destroyed easily by Overwhelming Odds: Lycan, Arc Warden, Warlock, Chen
Phantom Lancer
* Doom's Doom marks Phantom Lancer with a highly visible effect, and also silences and mutes him.
* Heroes with undispellable debuffs will help identify the real Phantom Lancer through visual effects or debuff indicators, provided that it was cast on the real Phantom Lancer to begin with:
* Doom's Doom marks Phantom Lancer with a highly visible effect, and also silences and mutes him.
* Bloodseeker's Rupture shows a clear red trail effect on the real Phantom Lancer.
* Ancient Apparition's Ice Blast will only debuff Phantom Lancer and not his illusions.
* Grimstroke's Soulbind is undispellable.
* Shadow Demon's Demonic Purge is undispellable.
* Monkey King's Jingu Mastery is undispellable and puts a big yellow Mark over his head.
Phantom Lancer
* Phantom Lancer's illusions can make it difficult to Doom the real hero. Should Doom figure out the real hero, the illusions can make it difficult to cast any abilities, as their hitboxes can be used to body-block the real Phantom Lancer.
* Phantom Lancer is an ideal Diffusal Blade carrier. With it, he can quite easily deplete Doom's already poor mana pool, potentially making him unable to cast his abilities to escape, retaliate or heal.
* Doom lacks any effective ability to clear waves of creeps and illusions, as the vast majority of his abilities are single-target. Without an answer, Doom may find it difficult to deal with Phantom Lancer's presence.
Legion Commander
* Heroes who can hide the Dueled target (Outworld Destroyer, Shadow Demon, Tusk, Phoenix with Aghanim's Scepter etc).
Additional:
* Walrus PUNCH! makes Legion Commander lose Duel easily, especially when she doesn't have Blade Mail. Tusk can also snowball dueled allies, preventing them from taking damage for a large portion of the duel's duration.
Phantom Lancer
* Doppelganger allows Phantom Lancer to dodge an incoming snowball.
* Phantom Lancer usually buys a Diffusal Blade, which is very effective against Tusk's low mana pool.
* Phantom Lancer usually buys Manta Style which can also dodge an incoming snowball, much like Doppelganger.
Phantom Lancer
* 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.
Legion Commander
* Duel is a great initiation to target Crystal Maiden with, as it prevents her from using Freezing Field or any other abilities and allowing the enemy team to quickly kill her before she can aid her team in a fight.
Legion Commander
* Heroes with abilities that blind or cause Legion Commander to miss will prevent her from winning Duels: Arc Warden, Keeper of the Light, Riki, Tinker
Legion Commander
* Another great threat to Riki since her Duel forces him to fight from the front and expose him for the entire duration, almost always guaranteeing an easy win (unless Riki has allies helping him).
* Moment of Courage can become hard to deal with as it doesn't cease with silence.
Phantom Lancer
* 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.
Legion Commander
* Press The Attack dispels the stun from Shackleshot.
* Duel can lock down Windranger before she can escape with Windrun.
* Legion Commander tends to go for Blade Mail, which returns the damage she takes from Focus Fire.
Phantom Lancer
* 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.
Phantom Lancer
* Doppelganger can be used to easily dodge Light Strike Array if timed correctly.
* While Lina can clear Phantom Lancer's illusions with her abilities, Phantom Lancer can quickly deplete Lina's mana pool with his illusions and deal massive damage from it simultaneously since Phantom Lancer is a natural Diffusal Blade carrier.
Legion Commander
* Wraith King's 
Reincarnation allows him to severely punish Legion Commander after he revives, as her abilities are on cooldown. Legion Commander is still awarded a Duel win if Wraith King reincarnates.
Additional:
* Wraith King makes a poor Duel target, as he can be already quite hard to bring down once, and then you have to worry about his second life.
* However, even if Legion Commander does win the duel when Reincarnation is off cooldown, she still receives the permanent victory damage bonus because taking down Wraith King's first life still counts as a "kill".
Phantom Lancer
* Diffusal Blade lets Phantom Lancer drain Wraith King's mana, preventing Reincarnation from triggering until he buys an Aghanim's Shard.
* Wraith King is bad against illusions-based heroes, as 
Wraithfire Blast is his only single-target disable and can get overwhelmed easily.
* Doppelganger can disjoint Wraithfire Blast.
Additional:
* Doppelganger disjoints Wraithfire Blast.
* Wraith King is not good at handling illusion-based heroes, as his only disable is single-target.
* Phantom Lancer tends to get Diffusal Blade, leaving Wraith King no mana to reincarnate until he has Aghanim's Shard.
Legion Commander
* Heroes with global abilities can give Legion Commander's opponent an edge in Duels from anywhere on the map: Nature's Prophet, Ancient Apparition, Zeus, Invoker, Treant Protector
Phantom Lancer
* Doppelganger can dispel Leech Seed. It can also destroy large amounts of trees, counteracting Nature's Guise and Eyes in the Forest.
Legion Commander
* Fate's Edict prevents Legion Commander from attacking for a few seconds, potentially saving Oracle's ally.
* Fortune's End dispels Press the Attack's healing and attack speed buff, as well as the movement speed bonus from Overwhelming Odds.
* False Promise protects allies and prevents Legion Commander from winning Duels and gaining bonus damage.
Additional:
* Provided that the enemy team does not have an Axe, Oracle can guarantee that his ally survives for the duration of the Duel with False Promise and has decent nuke potential to help ally to win a Duel. He can also disarm Legion Commander with Fate's Edict.
* Oracle can dispel enemy buffs like Overwhelming Odds and Press the Attack with Fortune's End.
Phantom Lancer
* Heroes who are not easily crippled by Fate's Edict or Fortune's End, such as Timbersaw, or those who can dispel them, such as Phantom Lancer, can kill Oracle unhindered.
Legion Commander
* Heroes with long disables, like Lion, 
Night Stalker, or Legion Commander, can prevent Oracle from using spells or items.
Phantom Lancer
* Bristleback's tankiness and damage reduction from the rear makes him very hard for Phantom Lancer to chase and finish off, due to his lack of burst damage.
* Quill Spray quickly destroys Phantom Lancer's illusions.
* Bristleback's passive costs no mana, meaning that it will continue to trigger even if Phantom Lancer drains Bristleback's mana with Diffusal Blade.
Additional:
* 
Bristleback's tankiness and damage reduction from the rear makes him very hard for Phantom Lancer to chase and finish off, due to his lack of burst damage.
* 
Quill Spray destroys Phantom Lancer's illusions.
* Bristleback's passive costs no mana, meaning that it will continue to trigger even if Phantom Lancer drains Bristleback's mana with Diffusal Blade.
Legion Commander
* Duel makes Bristleback fight Legion Commander face to face, forcing him to take full damage.
* Press the Attack dispels the slow from stacks of Viscous Nasal Goo.
Additional:
* When dueled, Bristleback will have to face Legion head on, not allowing his passive Bristleback to come into effect.
Legion Commander
* Heroes with global abilities can give Legion Commander's opponent an edge in Duels from anywhere on the map: Nature's Prophet, Ancient Apparition, Zeus, Invoker, Treant Protector
Legion Commander
* Legion Commander's Overwhelming Odds deals damage for every Treant it hits, which allows it to easily wipe out large waves of them.
Legion Commander
* 
Shallow Grave prevents Legion Commander from killing her opponents in Duels.
* 
Shadow Wave will heal an ally caught in a Duel, as well as dealing damage to Legion Commander.
Phantom Lancer
* Juxtapose and Doppelganger conjures too many illusions for Dazzle to deal with, given he has no inherent movement- or AoE-abilities.
* However, this can be partially solved with Aghanim's Shard-upgraded Poison Touch, as the hex instantly destroys illusions in an area as well as revealing the real Phantom Lancer when he's hiding among his army of illusions.
* Phantom Rush and Spirit Lance allow Phantom Lancer to trivially catch Dazzle even in the back line of a fight.
* Phantom Lancer has high base armor which counters Dazzle's physical damage based spells in lane.
* Diffusal Blade a natural item from Phantom Lancer can drains mana, which can be a problem for Dazzle, as all of his abilities have a high mana cost.
Legion Commander
* With armor items like 
Solar Crest or 
Assault Cuirass combined with Bash of the Deep, Slardar can easily tank the Duel, If not dueled himself, he can drop Legion Commander's armor during duel and/or buff his teammate and save them, leaving her only the choice of dueling supports which can also be saved with fast Blink into Slithereen Crush.
Phantom Lancer
* Phantom Lancer's Doppelganger has a low cooldown and applies a basic dispel on PL, making it hard to keep Corrosive Haze on him.
* Phantom Lancer usually purchases Manta Style which provides another basic dispel to remove Corrosive Haze with.
* Besides Slithereen Crush, Slardar does not have another way to deal with illusions and has a low mana pool, which allows Phantom Lancer with Diffusal Blade to quickly build up illusions while draining Slardar's mana.
* Phantom Rush outruns Guardian Sprint, forcing Slardar to Blink away or use Slithereen Crush defensively to avoid being killed.
Phantom Lancer
* 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).
Legion Commander
* A well-timed 
Eclipse before a Duel usually prevents Legion Commander from winning Duels, if Luna is the target.
* Meanwhile, when Luna is not a target, Eclipse and 
Lucent Beam can also help an ally win a Duel against Legion Commander.
* However, skilled Legion Commander will always buy a Black King Bar to block Eclipse and Lucent Beam or Aghanim's Scepter to reduce it's damage.
Additional:
* A well-timed Eclipse before a Duel usually prevents Legion Commander from winning Duels if Luna is the target. Luna can also buy Linken's Sphere to block Duel.
* Meanwhile, when Luna is not a target, Eclipse and Lucent Beam can also help an ally win a Duel against Legion Commander.
* Bear in mind, however, that skilled Legion Commander will always buy a Black King Bar to block Eclipse and Lucent Beam or Aghanim's Scepter to reduce their damage.
Phantom Lancer
* Even though Luna can clear Phantom Lancer's illusions with Moon Glaives, Phantom Lancer can create too many illusions to tank Luna's Eclipse and for Luna to handle overall.
* Doppelganger can be used to dodge a number of Lucent Beams during Eclipse.
* Phantom Lancer can chase Luna effectively regardless of her high movement speed thanks to Phantom Rush and Spirit Lance.
* Luna's low health pool is easily exploited by the sheer damage output from Phantom Lancer's illusions. Additionally, Phantom Lancer can often create more illusions for Luna to handle.
* For the same reasons, Phantom Lancer makes a very powerful ally for Luna when they are in the same team.
Legion Commander
* Heroes that can keep Luna locked down for a long time can be a threat (she is very item and spell dependent): Faceless Void, Legion Commander, Doom.
Legion Commander
* 
Decrepify on either hero stops Legion Commander from completing a Duel, and dissuades her from initiating Duels on ethereal allies.
* 
Life Drain can help Pugna's teammates win a fight, either by killing Legion Commander or replenishing her target's health.
Additional:
* Decrepify prevents Legion Commander from attacking allies during Duel, regardless if it's used on her or on the ally .
* Pugna can easily cast Decrepify, Nether Blast and Life Drain on Legion during the 4/4.75/5.5/8 seconds of duel
Phantom Lancer
* Phantom Lancer creates way too many illusions for Pugna's Life Drain to destroy, overwhelming him easily.
* Doppelganger can dodge 
Nether Blast or dispel Decrepify.
* Diffusal Blade is a common item for Phantom Lancer to burn Pugna's large mana pool and deals a large amount of damage in the process.
Additional:
* Though Life Drain instantly destroys illusions, Phantom Lancer creates way too many for Pugna to handle.
* A good Phantom Lancer will also dodge your Nether Blast with Doppelganger.
* Phantom Lancer is the most natural Diffusal Blade carrier to burn Pugna's very large pool of mana away and deal a large amount of damage in the process.
Phantom Lancer
* Charge of Darkness provides shared vision over its target, keeping track of heroes who rely on invisibility, mobility, or illusions: Riki, Broodmother, Phantom Lancer
Phantom Lancer
* 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.
Legion Commander
* Battery Assault's mini-stuns can severely disrupt Legion Commander's attack animation when she enters a Duel, potentially saving Clockwerk (or his allies) and possibly even giving him an edge in securing a win himself.
* Power Cogs pushes Legion Commander away from Clockwerk's allies when she enters a Duel.
Phantom Lancer
* Battery Assault's damage is dispersed against Phantom Lancer's illusions.
* Phantom Lancer can blink out of Power Cogs with Doppelganger.
* When chasing, a Phantom Lancer can close in with Phantom Rush and burn down Clockwerk's mana with Diffusal Blade, rendering him helpless before he has a chance to erect a defensive Power Cogs.
* Because Clockwerk does not like to buy items to deal with multiple enemies at once, like Battle Fury, Maelstrom and Mjollnir, he will be unable to deal with Phantom Lancer's illusions coming from Juxtapose.
Additional:
* Doppelganger. lets Phantom Lancer jump in and out of 
Power Cogs.
* Clockwerk's low mobility makes him an easy target for Phantom Lancer to rush on, and overwhelm with clones.
Legion Commander
* 
Astral Imprisonment prevents Legion Commander from killing her opponents in Duels.
Additional:
* Outworld Destroyer can save an ally hero caught by Duel with Astral Imprisonment, and he can inflict heavy damage on Legion Commander with Arcane Orb to aid his ally. However, if he gets caught, he is unlikely to survive the duel, due to his lack of durability.
Phantom Lancer
* Doppelganger and Juxtapose allow Phantom Lancer to initiate on Outworld Destroyer, and, although Arcane Orb will normally destroy his illusions instantly, Phantom Lancer will spawn too many to deal with without using Sanity's Eclipse.
* Outworld Destroyer has very little AOE ability; His Astral Imprisonment with Aghanim's Scepter is his primary AOE, and it does too little damage to eliminate Phantom Lancer's illusions.
Additional:
* Although Outworld Destroyer will typically destroy Phantom Lancer's illusions in one shot, Phantom Lancer spawns too many of them for Outworld Destroyer to deal with. However, be careful about initating on Outworld, as 
Sanity's Eclipse will erase your illusions and deal massive damage to you. He can then follow up with Astral Imprisonment and 
Meteor Hammer.
Phantom Lancer
* Bloodseeker's Rupture shows a clear red trail effect on the real Phantom Lancer.
* Heroes with undispellable debuffs will help identify the real Phantom Lancer through visual effects or debuff indicators, provided that it was cast on the real Phantom Lancer to begin with:
* Doom's Doom marks Phantom Lancer with a highly visible effect, and also silences and mutes him.
* Bloodseeker's Rupture shows a clear red trail effect on the real Phantom Lancer.
* Ancient Apparition's Ice Blast will only debuff Phantom Lancer and not his illusions.
* Grimstroke's Soulbind is undispellable.
* Shadow Demon's Demonic Purge is undispellable.
* Monkey King's Jingu Mastery is undispellable and puts a big yellow Mark over his head.
Phantom Lancer
* Heroes with illusion and clone abilities may confuse Bloodseeker, causing him to waste time in fights: Phantom Lancer, Chaos Knight, Arc Warden
Legion Commander
* Heroes with long or multiple disables will prevent Legion Commander from winning Duels: Shadow Shaman, Lion
Legion Commander
* Pudge, Legion Commander and Axe will make the match a living hell for Shadow Shaman, since they are known for surprise attacks from the fog and quickly killing low HP heroes. They can also interrupt Shadow Shaman's channeling, Legion being especially problematic, as she can use Press the Attack on an ally who is hexed as well.
Legion Commander
* 
Gravekeeper's Cloak protects Visage from Legion Commander's attacks for most of Duel's duration.
* Chain stuns from Visage's familiars prevents Legion Commander from winning Duels.
Phantom Lancer
* Phantom Lancer's illusions will quickly destroy multiple layers of Gravekeeper's Cloak.
* Visage has no mobility mechanisms, making him a prime target for Phantom Rush.
Legion Commander
* 
Mana Shield makes Medusa very hard to take down in Duels.
* 
Stone Gaze stops Legion Commander from Dueling altogether, regardless of who she targets.
Phantom Lancer
* Phantom Lancer with Diffusal Blade will very quickly burn Medusa's mana, making Mana Shield significantly less effective.
* Doppelganger's 1 second invulnerability can be used to dodge Medusa's petrification from Stone Gaze, as well as Mystic Snake.
* Phantom Lancer's illusions outnumber Medusa's targets from Split Shot, likely shielding his team in the process.
Legion Commander
* 
Fury Swipes can give Ursa the edge in Duels.
* Enrage's instant cast time allows it to be used before Legion Commander initiates a Duel, causing Ursa to take almost no damage for a brief period of time.
* However, Duel stops Ursa from casting Enrage at the most critical moment
Phantom Lancer
* Ursa has no sustained AoE to deal with illusions, it becomes worse since Phantom Lancer can create more illusions in a matter of seconds.
* Diffusal Blade can be used to drain Ursa mana. This is a standard item for Phantom Lancer in every match.
* Doppelganger applies basic dispel on Phantom Lancer, which will remove the slow from Earthshock. It also resets fights with more illusions, making hard for Ursa to hit the real Phantom Lancer.
* Manta Style creates two more illusions and also applies a basic dispel, further complicating the problem for Ursa to deal with.
Phantom Lancer
* Laser prevents Juxtapose from triggering, as it only triggers on successful attacks
* Laser does high splash, and upgrading it with Aghanim's Scepter makes it deal twice as much damage due to the bounce. Combined with Rearm, Tinker can rapidly deplete Phantom Lancer's illusion army
* However, if Phantom Lancer ambushes Tinker, Tinker will not survive versus Phantom Lancer.
Legion Commander
* Heroes with abilities that blind or cause Legion Commander to miss will prevent her from winning Duels: Arc Warden, Keeper of the Light, Riki, Tinker
Phantom Lancer
* 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.
Legion Commander
* Press the Attack can dispel Laser's blind while providing great attack speed and health regeneration.
* Once caught in a Duel, Tinker, who completely relies on his spells to be effective, has little chances of survival with his low health pool and armor.
Phantom Lancer
*
Great Cleave and 
God's Strength destroys illusions in just a few hits.
Storm Hammer's AoE stun will hit Phantom Lancer when he's grouped up with illusions.
Diffusal Blade. This is further reduced by the armor bonus from 
Warcry.
*
* Sven's low mana causes him to take less damage from
Additional:
* Great Cleave and God's Strength cuts through Phantom Lancer's illusions in no time.
* Storm Hammer's AoE stun will hit Phantom Lancer and his illusions.
Legion Commander
*
God's Strength makes Sven one of the worst heroes to Duel.
Storm Hammer can be used to interrupt Duels.
Warcry gives a big boost in passive defensive ability with the active component to nearby allies.
*
*
* With the Aghanim Shard Warcry also gives nearby allies passive increases.