Centaur Warrunner
* 
Winter Wyvern's 
Arctic Burn can also be a useful tool against Centaur, who generally has very high health. 
Winter's Curse on Centaur can cause Retaliate to damage allies who are forced to attack him.
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.
Centaur Warrunner
* Luna's 
Moon Glaives will not trigger 
Retaliate if they hit some other target first. Also Luna commonly buys items that provide lifesteal such as 
Satanic, which lets her heal from the damage of Retaliate, meaning that Retaliate has little effect against her.
* 
Eclipse can be used to counter-initiate against Centaur Warrunner after he jumps in with 
Blink Dagger, and initiates with 
Hoof Stomp. But remember that Centaur Warrunner can resolve this problem by buying 
Hood of Defiance and it's upgrade 
Pipe of Insight to diminish its damage. Or 
Blade Mail to reflect the damage of the Eclipse back at Luna.
* Luna also commonly buys 
Black King Bar, which will allow her to protect herself from both, Centaur Warrunner's abilities (except for the Retaliate), and damage reflect from Blade Mail.
Additional:
* Luna's Moon Glaives will not trigger Retaliate if they hit some other target first. Also Luna commonly buys items that provide lifesteal such as Satanic, which lets her heal from the damage of Retaliate, meaning that Retaliate has limited effect against her.
* Eclipse can be used to counter-initiate against Centaur Warrunner after he jumps in with Blink Dagger, and initiates with Hoof Stomp. But remember that Centaur Warrunner can resolve this problem by buying Hood of Defiance and it's upgrade Pipe of Insight to diminish its damage. Or Blade Mail to reflect the damage of the Eclipse back at Luna.
* Luna also commonly buys Black King Bar, which will allow her to protect herself from both, Centaur Warrunner's abilities (except for the Retaliate), and damage reflect from Blade Mail.
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.
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
* 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.
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
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.
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.
Centaur Warrunner
* 
Feast is an effective tool against Centaur Warrunner, who generally has high health and low armor, and compensates the reflected damage of Retaliate.
* If activated, 
Rage can protect Lifestealer from Hoof Stomp, Double Edge, and Stampede.
Additional:
* Centaur Warrunner's active abilities cannot pierce magic immunity. Hoof Stomp's slow wind up can also be anticipated and negated with Rage.
* Lifestealer can offset Retaliate's damage return simply with Feast. Centaur's high strength gain and therefore big health pool makes him an ideal target to Feast on, especially in the late-game.
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.
Centaur Warrunner
* Decay can be good against Centaur Warrunner, as reducing the health of Centaur can make 
Double Edge risky.
* His zombies do not proc Retaliate, as it only procs for regular attacks.
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.
Legion Commander
* Earthshaker's AoE stuns can save ally against Duel, forcing Legion Commander to spend Aghanim's Scepter or Black King Bar.
Centaur Warrunner
* 
X Marks the Spot negates Stampede.
Legion Commander
* 
Mystic Flare can easily burst down Legion Commander while she is Dueling.
Centaur Warrunner
* 
Kinetic Field and 
Glimpse can completely negate Stampede.
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.
Legion Commander
* Solar Guardian can save allies who are being dueled and will interrupt her Duel initiation.
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
Centaur Warrunner
* With high health and rarely buying Linken's Sphere or Black King Bar, Centaur Warrunner is a good target for 
Reaper's Scythe. However, Centaur Warrunner can resolve this problem by buying Hood of Defiance and it's upgrade Pipe of Insight to diminish its damage.
* 
Heartstopper Aura will do well against high health heroes such as Centaur Warrunner.
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.
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.
Centaur Warrunner
* Centaur has nothing to deal with 
Refraction that will negate all of his burst damage.
* 
Psionic Traps provide good vision, making for him harder to initiate.
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
* 
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".
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.
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.
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
* 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.
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
* 
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.
Legion Commander
* Heroes with long disables, like 
Lion, 
Night Stalker, or Legion Commander, can prevent Oracle from using spells or items.
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.
Centaur Warrunner
* Heroes who thrive on teamfights can be a problem, such as 
Venomancer, 
Necrophos, 
Centaur Warrunner...
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.
Legion Commander
* Heroes with strong dispels can dispel Bane's disables from their allies: 
Oracle, Legion Commander, 
Omniknight.
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
* 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.
Centaur Warrunner
* 
Headshot and 
Shrapnel slow is ineffective against a team with haste (which Stampede gives).
* Commonly picked up mobility items and hasted movement during his Stampede (as well as his high health pool) make him extremely hard to kill from a distance, damaging 
Sniper with Retaliate and Blade Mail if he has one.
* A low health pool and no escape mechanism makes him an easy target for Centaur Warrunner's burst damage and initiation (even making his team possible initiators with Stampede).
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.
Centaur Warrunner
* A good Centaur can catch Queen of Pain with a Blink Dagger and Hoof Stomp.
* Retaliate with Blade Mail reflects all of Queen of Pain's damage, especially Sonic Wave.
* 
Stampede grants a movement speed bonus, which can prevent Queen of Pain from initiating.
* Double Edge can shred her low health pool if she's not careful.
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.
Centaur Warrunner
* Centaur's low Intelligence makes 
Mind Flare do low damage.
* With some creative skill builds, Centaur's Hoof Stomp stun duration should always last longer than 
Spiked Carapace stun, so escaping unscathed is hard for Nyx.
* With Blink Dagger and detection, Centaur can devastate Nyx in the open.
* However, bear in mind that Nyx can also easily initiate on Centaur Warrunner as well if he uses Spiked Carapace in anticipation, and with 
Vendetta. The damage from Retaliate will be reflected back to Centaur Warrunner, stunning him with no chance to react after he's revealed himself, and should guarantee a successful 
Impale.
Legion Commander
* Duel's long duration prevents Nyx Assassin escaping from Vendetta. With Aghanim's Scepter, she can also bypass Spiked Carapace.
Centaur Warrunner
* 
Focus Fire grants Windranger a massive attack speed bonus, while her attack damage is generally quite low. This, combined with Windranger's low health pool and armor, makes Retaliate do absolutely massive damage over a short time, making Centaur a hero she can never expect to kill or harass.
* 
Windrun grants evasion, but Centaur Warrunner does not rely on successful attacks in order to do damage. Hoof Stomp, Double Edge, and Stampede all do large amounts of magical damage and can completely demolish Windranger in a moment.
Additional:
* Stampede can help his teammates escape from Windrun and Focus Fire.
* Retaliate will shred through Windranger's health if she chooses to attack him during Focus Fire.
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.
Centaur Warrunner
* 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.
Legion Commander
* Heroes who rely on illusions will see them destroyed easily by Overwhelming Odds: 
Phantom Lancer, 
Chaos Knight, 
Terrorblade, 
Naga Siren
Additional:
* Overwhelming Odds deals high damage to Phantom Lancer's illusions.
* Duel's long duration prevents Phantom Lancer from using Doppelganger.
Centaur Warrunner
* As Terrorblade's damage output comes mainly from direct attacks, he will struggle greatly against heroes who have abilities that give evasion, trigger on attack or which can disarm an enemy hero: Centaur Warrunner, 
Hoodwink, 
Huskar, Invoker, 
Leshrac with 
Nihilism from Aghanim's Scepter, 
Lifestealer with Aghanim's Scepter upgraded 
Infest, 
Pangolier, 
Phantom Assassin, 
Pugna, 
Techies, 
Windranger etc.
Legion Commander
* Duel's long duration prevents Terrorblade from swapping his health with 
Sunder.
* Overwhelming Odds deals high damage to Terrorblade's illusions.
Centaur Warrunner
* 
Anti-Mage's 
Mana Void won't do a lot of damage because Centaur has a low mana pool. 
Mana Break is also relatively ineffective against him.
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.
Centaur Warrunner
* Heroes who have low or high armor but very high health will be difficult for drow to burst down quickly: 
Primal Beast, Axe, Centaur Warrunner.
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.
Centaur Warrunner
* Heroes who are reliant on illusions: Chaos Knight, Phantom Lancer, Naga Siren.
Legion Commander
* Heroes with strong area damage to destroy Phantasm illusions: Axe, 
Ember Spirit, Legion Commander, Phoenix
Centaur Warrunner
* Heroes who can match Void Spirit's mobility (like the aforementioned Ember Spirit or 
Queen of Pain) or tank his spells (
Dragon Knight or Centaur Warrunner) are very problematic for him.
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
* Press the Attack dispels Flaming Lasso.
* Batrider is unlikely to win a Duel in any stage of the game.
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.
Centaur Warrunner
* Whenever Doom casts his ultimate, Centaur Warrunner can cast Stampede and allow the 
Doomed hero to run away, wasting Doom's ultimate.
Additional:
* Stampede can be used to free an ally from the grasp of Doom. Without any means of effective lockdown, kills can be difficult to secure when against an enemy Centaur Warrunner. Also, Centaur's tendency to have lots of health and HP regen tend to help counter Doom.
Centaur Warrunner
* Stampede can allow Soulbinded heroes to just ran away.
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
* 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
* 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.
Legion Commander
* Duel pierces spell immunity and forces him to attack Legion Commander, making him unable to use 
Omnislash.
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.
Centaur Warrunner
* Hoof Stomp and Double Edge can often burst down Phantom Assassin from early to mid game.
* Retaliate makes it very unlikely for Phantom Assassin to win the lane against Warrunner. Double Edge can also be used to wear her down, as she has a much smaller health pool than that of Centaur Warrunner until purchasing a 
Ring of Health. 
Stifling Dagger will also trigger Retaliate and 
Blur cannot evade Retaliate.
* Centaur Warrunner's tankiness in combination with armour items that Axe often purchases like Blade Mail, 
Crimson Guard, Assault Cuirass and 
Shiva's Guard can make Phantom Assassin's attacks only tickle Centaur Warrunner.
* Centaur Warrunner just has to be careful about 
Fan of Knives from 
Aghanim's Shard and 
Coup De Grace, as Fan of Knives can disable Retaliate even if Centaur Warrunner is spell immune.
Additional:
* Hoof Stomp and Double Edge can often burst down Phantom Assassin from early to mid game.
* Retaliate makes it very unlikely for Phantom Assassin to win the lane against Warrunner. Double Edge can also be used to wear her down, as she has a much smaller health pool than that of Centaur Warrunner until purchasing a Ring of Health. Stifling Dagger will also trigger Retaliate and Blur cannot evade Retaliate.
* Centaur Warrunner's tankiness in combination with armour items that Centaur Warrunner often purchases like Blade Mail, Crimson Guard, Assault Cuirass and Shiva's Guard can make Phantom Assassin's attacks only tickle Centaur Warrunner.
* Centaur Warrunner just has to be careful about Fan of Knives from Aghanim's Shard and Coup De Grace, as Fan of Knives can disable Retaliate even if Centaur Warrunner is spell immune.
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.
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.
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.
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
* 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.
Centaur Warrunner
* Heroes with haste can negate Enchant's slow: 
Weaver, 
Dark Seer, 
Lycan, Centaur Warrunner.
Centaur Warrunner
* Axe, 
Bristleback, Centaur Warrunner, Spirit Breaker, 
Pudge, Huskar, Wraith King, Doom: These heroes are too tanky for Puck to burst down. Also, all of them have spells which can deal with and shut Puck down reliably.
Legion Commander
* Heroes who rely on summons will see them destroyed easily by Overwhelming Odds: Lycan, 
Arc Warden, 
Warlock, 
Chen
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.
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
Centaur Warrunner
* Heroes that can stop Faceless Void from leaping around the fight and controlling its outcome are very strong against him. Heroes such as: Axe, Centaur Warrunner, Doom...
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.
Legion Commander
* 
Tethered heroes are much harder for Legion Commander to kill in Duels.
* 
Relocate can cancel Duels and save allies.
Centaur Warrunner
* Heroes that are hard to gank: Axe, 
Death Prophet, Phantom Lancer, 
Slark, Centaur Warrunner, Bristleback, 
Medusa, 
Mars.
Legion Commander
* Duel is very effective against Io due to its low health and armor.
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 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
* 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.
Centaur Warrunner
* Night Stalker is all about right-clicks. His nuke, 
Void is also not that threatning once you have Hood of Defiance, your core item.
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.
Legion Commander
* Magnetic Field prevents Legion Commander from getting wins with Duel.
Additional:
* 
Magnetic Field prevents Legion Commander from easily gaining wins with Duel.
Centaur Warrunner
* Arc Warden cannot take Centaur Warrunner very easily, and his nukes are not strong enough to deal with Centaur Warrunner.
* Centaur Warrunner deals huge AoE damage and applies an AoE disable through Hoof Stomp, affecting the double as well the main Arc Warden.
* Magnetic Field is not very effective against melee heroes. And to make things worse, Magnetic Field also increases Arc Warden and his allies's attack speed, meaning Retaliate will deal more damage.
* Stampede catches Arc Warden easily due to his lack of escape mechanisms. However, Arc Warden can counter this problem with 
Gleipnir, which is a common item on Arc Warden.
Legion Commander
* Heroes who rely on summons will see them destroyed easily by Overwhelming Odds: Lycan, Arc Warden, Warlock, Chen
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
* 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.
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.
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
* 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.
Legion Commander
* Song of the Siren lasts long enough to prevent a successful Duel (but only if Naga wasn't the target).
Centaur Warrunner
* Heroes who are reliant on illusions: Chaos Knight, Phantom Lancer, Naga Siren.
Additional:
* Centaur's Retaliate will harm all attacking enemies, which will allow Centaur Warrunner to see which is the real Naga Siren.
* A well timed Hoof Stomp followed by Double Edge will clear all Naga's illusions and prevent Naga Siren from escaping with 
Song of the Siren.
Legion Commander
* Heroes who rely on illusions will see them destroyed easily by Overwhelming Odds: Phantom Lancer, Chaos Knight, Terrorblade, Naga Siren
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
Centaur Warrunner
* Heroes that can keep Monkey King stunned for a long time can pose a threat: Axe, Centaur Warrunner.
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.
Centaur Warrunner
* Pangolier will proc Retaliate several times if he attempts to use Swashbuckle on Centaur Warrunner.
* Centaur can cast Stampede to allow all of his allies to easily avoid Rolling Thunder.
* Centaur's tankiness makes it hard for Pangolier to burst him down in the late game.
Additional:
* When Swashbuckle hits Centaur Warrunner, Retaliate will deal significant damage, as it procs off every strike made.
* Stampede helps allies avoid or disengage from Pangolier during Rolling Thunder, as well as neutralizing the slow debuff from Lucky Shot.
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.
Centaur Warrunner
* Durable heroes can stand against Tusk during 1v1: Axe, Dragon Knight, Night Stalker, Centaur Warrunner, Wraith King and more.
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.
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 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
* 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.
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.
Centaur Warrunner
* Centaur can use Stampede to break Static Link. It also prevents Razor from chasing Centaur Warruner or his teammates with Eye of the Storm, and Plasma Field's slow will do nothing to slow them down.
Legion Commander
* Troll Warlord's melee bash and high attack speed can often help him and his allies win Duels against Legion Commander.
Centaur Warrunner
* Troll Warlord's high speed attack makes Retaliate deal a lot of damage to him.
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.
Centaur Warrunner
* Centaur Warrunner's passive Retaliate makes it so that the familiars cannot attack him without damaging themselves over time, in turn causing them to be destroyed.
Centaur Warrunner
*
Battery Assault easily interrupts Centaur Warrunner due to his poor cast animation.
Power Cogs can negate Stampede.
*
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.
Duel.
* Power Cogs pushes Legion Commander away from Clockwerk's allies when she enters a