Venomancer
* 
Borrowed Time & 
Aphotic Shield can dispel Venomous Gale and Poison Sting.
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.
Venomancer
* Snowball can be used to save allies or himself during 
Venomous Gale and 
Poison Nova.
* Venomancer lacks mobility and has low base health, so he can be killed by Walrus PUNCH!
Legion Commander
* 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.
Venomancer
* While 
Reincarnation is off cooldown, Poison Nova poses less of a threat as Wraith King will return with all debuffs cleared.
* 
Vampiric Spirit can out-heal the slow {tooltip:DoT|Damage over Time} from Poison Sting.
Legion Commander
* 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".
Venomancer
* In the laning stage, making illusions of Venomancer will turn his 
Poison Sting back at him, making for an easy gank at level one, and for later when your mid comes for ganks.
Legion Commander
* 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.
Venomancer
* Venomancer's damage-over-time abilities are easier to heal through with numerous Shadow Waves than other types of damage, and it's simple to time a Shallow Grave until the last possible second to save a teammate from 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.
Venomancer
* Any hero that can outrange Plague Ward can neutralize them without putting themselves at risk of receiving Poison Sting: 
Arc Warden, 
Chen, 
Clinkz, 
Drow Ranger, 
Lina, 
Mirana, 
Nature's Prophet, 
Pugna and 
Sniper.
* Special mention to heroes that outrange Plague Ward after obtaining talents that increase attack range.
Legion Commander
* 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
Additional:
* 
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.
Venomancer
* 
Slardar can attack through Plague Wards and gain 
Bash of the Deep charges, and 
Templar Assassin can spill 
Psi Blades through Plague Wards too.
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.
Venomancer
* 
Fortune's End can dispel Venomous Gale and Poison Sting from allies.
* 
Fate's Edict grants 100% magic resistance to target, inhibiting the damage from Venomancer abilities.
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.
Venomancer
* 
Dark Rift allows Underlord to transport allies from poison damage-over-time to the fountain.
* Underlord usually buys 
Pipe of Insight that gives a magic resistance to allies, inhibiting the damage from Venomancer abilities.
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.
Venomancer
* Heroes with strong area-of-effect damaging and/or disabling abilities will be able to intercept Underlord and his team when they exit from Fiend's Gate: 
Luna's 
Aghanim's Scepter upgraded 
Eclipse, 
Dawnbreaker's 
Solar Guardian, Axe's 
Berserker's Call, 
Mars's 
Arena of Blood, 
Jakiro's 
Macropyre, 
Dual Breath and 
Ice Path, 
Naga Siren's 
Song of the Siren, 
Razor's 
Eye of the Storm and 
Plasma Field, Lina's 
Light Strike Array, 
Broodmother's 
Spinner's Snare from Aghanim's Scepter, 
Elder Titan's 
Earth Splitter and 
Echo Stomp, 
Alchemist's 
Unstable Concoction and 
Acid Spray, 
Queen of Pain's 
Sonic Wave, 
Dark Seer's 
Wall of Replica and 
Vacuum, 
Venomancer's 
Noxious Plague and Poison Nova from Aghanim's Scepter, 
Oracle's Fortune's End and 
Rain of Destiny from 
Aghanim's Shard, 
Bloodseeker's 
Blood Rite, 
Enigma's 
Black Hole and 
Midnight Pulse, 
Shadow Fiend's 
Requiem of Souls, 
Batrider's Aghanim's Scepter upgraded 
Flaming Lasso, 
Firefly, 
Flamebreak and 
Sticky Napalm, 
Ancient Apparition's 
Ice Blast, 
Sand King's 
Epicenter, 
Sand Storm and 
Burrowstrike, 
Gyrocopter's 
Call Down, 
Ember Spirit's 
Sleight of Fist, 
Death Prophet's 
Exorcism and 
Silence, 
Monkey King's 
Wukong's Command, 
Crystal Maiden's 
Freezing Field, 
Muerta's 
The Calling, 
Medusa's 
Stone Gaze, 
Zeus's 
Nimbus from Aghanim's Scepter. 
Dark Willow's 
Bramble Maze, 
Pangolier's 
Swashbuckle, 
Grimstroke's 
Soulbind, 
Ink Swell and 
Stroke of Fate, 
Earthshaker's 
Echo Slam and 
Fissure, 
Puck's 
Dream Coil and 
Waning Rift, 
Winter Wyvern's 
Winter's Curse, 
Magnus's 
Reverse Polarity.
Venomancer
* Venomancer has low health, which makes him vulnerable to Lina's heavy magic damage.
* Fiery Soul attack speed bonus removes 
Plague Wards easily in all stages of the game.
Venomancer
* 
Dark Pact can dispel Venomous Gale and Poison Sting.
* 
Shadow Dance allows Slark heightened regeneration when out of vision making DoTs effects less threatening.
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
* 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.
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.
Venomancer
* Venomancer is a low health hero and low range hero who is easy to harass with Ion Shell on a creep in the early game.
* Venomancer depends entirely on all his slows to keep distance or chase, but since Surge ignores slows, it is nearly impossible for Venomancer to hunt or run away from Dark Seer or his surged teammates.
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.
Legion Commander
* 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.
Additional:
* 
Astral Imprisonment prevents Legion Commander from killing her opponents in Duels.
Venomancer
* Any hero that can outrange Plague Ward can neutralize them without putting themselves at risk of receiving Poison Sting: Arc Warden, Chen, Clinkz, Drow Ranger, Lina, Mirana, Nature's Prophet, Pugna and Sniper.
* Special mention to heroes that outrange Plague Ward after obtaining talents that increase attack range.
Legion Commander
* 
Magnetic Field prevents Legion Commander from easily gaining wins with Duel.
Additional:
* Magnetic Field prevents Legion Commander from getting wins with Duel.
Legion Commander
* Heroes who rely on summons will see them destroyed easily by Overwhelming Odds: 
Lycan, Arc Warden, 
Warlock, Chen
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.
Legion Commander
* 
Mystic Flare can easily burst down Legion Commander while she is Dueling.
Venomancer
* Squishy heroes or heroes without hard disables or silences: 
Shadow Demon, Shadow Fiend, Venomancer, Ancient Apparition etc.
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
* 
Troll Warlord's melee bash and high attack speed can often help him and his allies win Duels against Legion Commander.
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.
Venomancer
* Any hero that can outrange Plague Ward can neutralize them without putting themselves at risk of receiving Poison Sting: Arc Warden, Chen, Clinkz, Drow Ranger, Lina, Mirana, Nature's Prophet, Pugna and Sniper.
* Special mention to heroes that outrange Plague Ward after obtaining talents that increase attack range.
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
* Clinkz, Sniper, 
Lone Druid, Troll Warlord, Legion Commander and 
Wraith King are some of the Heroes that base themselves on attacks with little or no spell power, so they suffer in the grassy hands of Overgrowth.
Legion Commander
* Legion Commander is unlikely to win a Duel against Ursa.
Additional:
* 
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
Venomancer
* Any hero that can outrange Plague Ward can neutralize them without putting themselves at risk of receiving Poison Sting: Arc Warden, Chen, Clinkz, Drow Ranger, Lina, Mirana, Nature's Prophet, Pugna and Sniper.
* Special mention to heroes that outrange Plague Ward after obtaining talents that increase attack range.
Additional:
* Teleportation allows Natures Prophet to save himself from the damage over time of Venomous Gale, Poison Sting and Poison Nova.
* Plague Wards can be destroyed with Nature's Prophet's Treants.
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 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
* 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.
Venomancer
* Sniper can easily destroy Plague Ward from long range.
Legion Commander
* Heroes who have high health are a problem for Sniper because he likes to attack the closest target and sit at the back, much like a 
Terrorblade so when that hero doesn't die; he's forced to show his position for a very long time: 
Centaur Warrunner, Legion Commander, 
Primal Beast.
Additional:
* 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.
Legion Commander
* Solar Guardian can save allies who are being dueled and will interrupt her Duel initiation.
Venomancer
* Due to her slow movement speed,heroes with crowd control and slows can shut down Dawnbreaker:Lion, Crystal Maiden ,Venomancer etc.
Venomancer
* Huskar can easily regenerate lost health from DoT spells through 
Berserker's Blood rendering them ineffective
* Venomancer has little armor and mobility, and rarely builds Linken's Sphere, so he is quite vulnerable to 
Life Break.
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
* 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
* 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.
Additional:
* 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.
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.
Venomancer
* All of Venomancer's abilities are decent choices for Rubick's 
Spell Steal. Stealing Plague Wards makes them apply Poison Sting as well.
Additional:
* Venomous Gale is a great ganking and farming skill.
* Plague Ward serves as a flexible ability for pushing, ganking, farming and scouting. The innate Poison Sting also works on the stolen Plague Ward with half the damage.
* Poison Nova, if stolen and cast, puts a huge damage-over-time debuff on the enemy team, even greater than Venomancer himself with the help of 
Arcane Supremacy.
* Spell Steal has a greater cast distance than the effect area of Poison Nova, allowing Rubick to steal the spell while staying at the back.
* Venomancer suffers from mana pool problems, while Rubick has relatively high intelligence gain and can cast the same set of spells at ease.
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
* 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
Legion Commander
* Both Guardian Angel and Purification are perfect counters against Duel.
Additional:
* 
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.
Venomancer
* Heroes who can harass Omniknight out of lane will keep him weak in the mid game: 
Viper, Venomancer, Clinkz.
Venomancer
* Plague Wards are very hard for Batrider to play against as they provide a lot of vision as well as disable Blink Dagger for a long duration.
Legion Commander
* Press the Attack dispels Flaming Lasso.
* Batrider is unlikely to win a Duel in any stage of the game.
Venomancer
* Due to lack of magic resistance, Venomancer abilities eats through Windranger's health.
* Venomancer's multiple slows, to an extent, negates Windrun's mobility.
Additional:
* Due to lack of magic resistance, Venomancer poisons eats through Windranger's health.
Legion Commander
* Press The Attack can save her allies 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.
Venomancer
* Plague Wards may reveal a hiding Techies. If there's a sentry nearby, they may also reveal a stack of mines hidden in a juking spot.
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
Venomancer
* Venomancer's slows and magical damage-over-time work well against Axe's complete lack of mobility.
* Plague Ward is especially useful for slowing down Axe, and revealing him before he initiates, as well as putting his Blink Dagger on cooldown.
Additional:
* Venomancer's slows and magical damage-over-time work well against Axe's complete lack of mobility.
* Plague Wards is especially useful for slowing down Axe, and revealing him before he initiates, as well as putting his Blink Dagger on cooldown.
* For the same reasons, Venomancer is a good ally for Axe when the situation is reversed.
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.
Venomancer
* Venomancer's magical damage-over-time poisons greatly reduce Bounty Hunter's mobility.
* Venomous Gale, combined with Plague Wards and Poison Nova with True Sight items can allow Venomancer and his teammates to gank Bounty Hunter while he is roaming alone.
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.
Venomancer
* Any hero that can outrange Plague Ward can neutralize them without putting themselves at risk of receiving Poison Sting: Arc Warden, Chen, Clinkz, Drow Ranger, Lina, Mirana, Nature's Prophet, Pugna and Sniper.
* Special mention to heroes that outrange Plague Ward after obtaining talents that increase attack range.
Venomancer
* Venomancer's damage over time can force Chen to use Hand of God prematurely, potentially wasting a chance to save his allies during a teamfight.
* Venomancer's Poison Nova, Venomous Gale and Plague Ward can easily kill Chen's 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.
Venomancer
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: Jakiro, Viper, Venomancer, Huskar, Ember Spirit, Dark Seer, Sand King, Doom, Dawnbreaker. However, this also means they are easily stunned.
Legion Commander
* Heroes who build Black King Bar as either core or situational item will be able to fight back against Nyx Assassin and freely attack him as Spiked Carapace cannot pierce spell immunity at all: Axe, Broodmother, Dawnbreaker, Enigma, Huskar, Jakiro, Legion Commander, Lina, Luna, Lycan, Slardar, Slark, Troll Warlord, 
Witch Doctor.
Additional:
* Duel's long duration prevents Nyx Assassin escaping from 
Vendetta. With Aghanim's Scepter, she can also bypass 
Spiked Carapace.
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.
Venomancer
* Venomancer's poison damage-over-time are very effective against Spectre, which is lack of magic resistance from early to mid game.
* Venomancer's multiple slows greatly reduces Spectre's low mobility, even through 
Spectral Dagger.
* Plague Wards reveals Spectre while she is hiding on trees.
Additional:
* Venomancer's poison damage over time is very effective against Spectre, who tends to lack magic resistance during the early to mid game.
* Venomancer's multiple slows greatly reduces Spectre's movement speed and mobility.
* Plague Wards can scout out Spectre while she is hiding in trees.
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
* 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
* 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
* Duel pierces spell immunity and forces him to attack Legion Commander, making him unable to use 
Omnislash.
Venomancer
* Venomancer can simultaneously scout Magnus hiding in trees and putting Blink Dagger on cooldown with Plague Wards, which makes Magnus real problems to blink and initiate.
Additional:
* Similar to Night Stalker, Venomancer can simultaneously scout Magnus hiding in trees and put Blink Dagger on cooldown with Plague Ward, which gives Magnus problems when trying to blink in and initiate.
Legion Commander
* Overwhelming Odds deals high damage to Phantom Lancer's illusions.
* Duel's long duration prevents Phantom Lancer from using Doppelganger.
Venomancer
* Unless Puck is facing the direction he wants to blink while in Phase Shift, the Venomous Gale and Noxious Plague combo consistently ticks many times over several seconds, making it very difficult to use Blink Dagger towards the other direction. Puck's slow turning rate makes this even worse.
* Venomancer can use Plague Wards to reveal Puck's position before he even gets a chance to initiate.
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
* Silences and other types of lockdown that prevent Weaver from using his spells: 
Silencer, 
Riki, Lion, Legion Commander, Shadow Shaman, Bane.
Additional:
* Duel's long duration prevents Weaver from activating Time Lapse or escaping with 
Shukuchi.
Legion Commander
* Heroes who rely on summons will see them destroyed easily by Overwhelming Odds: Lycan, Arc Warden, Warlock, Chen
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.
Venomancer
* Heroes that can slow Charge of Darkness by a huge amount: Venomancer, Viper, 
Dazzle, Arc Warden, Lion, Huskar, Shadow Shaman, 
Visage, 
Undying, Jakiro.
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.
Venomancer
* Heroes that can apply early pressure before Phantom Assassin has farm are massive threats: Axe, Viper, 
Meepo, Jakiro, Pugna, Slark, Venomancer etc.
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
Venomancer
* Heroes that commonly attack ethereal units will not have any problems against Muerta's Pierce The Veil: 
Tinker, Jakiro, Lina, Luna, Pugna or Ogre Magi, Enigma, Batrider, Techies, Broodmother, Dawnbreaker, Shadow Shaman, Bane, Tinker, Venomancer, Arc Warden.
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.
Venomancer
* Venomancer's poison attacks are all magical damage, ignoring Bulwark.
* Venomancer's multiple slows are especially effective against Mars' low mobility.
* Plague Wards can attack through Arena of Blood.
Additional:
* Venomancer's spells all deal magical damage, ignoring Bulwark.
* Venomancer's multiple slows are especially effective at kiting Mars.
* Plague Ward can attack through Arena Of Blood.
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.
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
Venomancer
* In general, heroes that can slow down Dragon Knight's movement speed will do well against him. This includes Venomancer and others in addition to the heroes mentioned above.
Legion Commander
* Heroes with strong area damage to destroy Phantasm illusions: Axe, Ember Spirit, Legion Commander, Phoenix
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 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.
Venomancer
* Any hero that can outrange Plague Ward can neutralize them without putting themselves at risk of receiving Poison Sting: Arc Warden, Chen, Clinkz, Drow Ranger, Lina, Mirana, Nature's Prophet, Pugna and Sniper.
* Special mention to heroes that outrange Plague Ward after obtaining talents that increase attack range.
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.
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 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
Venomancer
* Venomancer's magical damage-over-time poisons putting 
Tree Dance on cooldown, greatly diminishing Monkey King's mobility.
* Venomous Gale and Posion Nova will hit Monkey King when he is perched on a tree, or disguised by 
Mischief.
Additional:
* Venomancer's magical damage-over-time poisons will constantly put Tree Dance on cooldown, greatly diminishing Monkey King's mobility.
* Venomous Gale and Poison Nova will hit Monkey King when he is perched on a tree, or disguised with Mischief.
* However, Venomancer is also easily ganked by Monkey King if caught by surprise.
Venomancer
* Any hero that can outrange Plague Ward can neutralize them without putting themselves at risk of receiving Poison Sting: Arc Warden, Chen, Clinkz, Drow Ranger, Lina, Mirana, Nature's Prophet, Pugna and Sniper.
* Special mention to heroes that outrange Plague Ward after obtaining talents that increase attack range.
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.
Venomancer
* Heroes with damage-over-time abilities easily allow Bristleback to turn his back in order to proc 
Bristleback continuously and to massively reduce to damage dealt to him: Arc Warden, Venomancer, Luna.
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.
Venomancer
* Slardar can attack through Plague Wards and gain Bash of the Deep charges, and Templar Assassin can spill Psi Blades through Plague Wards too.
Venomancer
* Venomous Gale and Plague Wards allow to quickly melt through 
Refraction charges.
* Both Poison Nova and Venomous Gale hit invisible units, so 
Meld cannot be used defensively.
Additional:
* Venomancer's entire arsenal deals lingering damage over a long time and therefore burns through her Refraction very quickly. Not only that, his persistent slow from Poison Sting (it can be re-applied again and again with Plague Ward) allows his team to catch up to her even with the disruption from her Psionic Trap.
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
* 
Tethered heroes are much harder for Legion Commander to kill in Duels.
* 
Relocate can cancel Duels and save allies.
Legion Commander
* Duel is very effective against Io due to its low health and armor.
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
* 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.
Venomancer
* Aggressively Poofing and Earthbinding is not going to end well against Venomancer, as he will be an easy target for Noxious Plague.
* Venomancer's constant slows greatly reduce Meepo's mobility.
Legion Commander
* Strong laners are usually at a disadvantage because of how well Sven can jungle. Heroes such as Dark Seer. 
Underlord and Legion Commander may find that later Sven takes care of them very quickly after some jungle farming.
Additional:
* 
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.
Venomancer
* Heroes who thrive on teamfights can be a problem, such as Venomancer, 
Necrophos, Centaur Warrunner...
Venomancer
* 
Reflection illusion will apply Poison Sting back towards Venomancer.
* 
Conjure Image and 
Metamorphosis will make quick work of Plague Wards.
* While ticking down from Poison Nova, Terrorblade can wait until the last possible moment to 
Sunder a target, either friend or foe.
Legion Commander
* Duel's long duration prevents Terrorblade from swapping his health with Sunder.
* Overwhelming Odds deals high damage to Terrorblade's illusions.
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.
Venomancer
* Venomous Gale, Poison Sting and Poison Nova deal damage over time and will chip away at Gravekeeper's Cloak in addition to slowing an already sluggish hero.
* Venomancer's normal attacks deal Poison Sting and will chip away at Gravekeeper's Cloak.
Venomancer
* 
Corrosive Skin means Viper can often outlast Venomancer in a battle of attrition.
* Venomancer has no mobility without items, which makes him vulnerable to constant slows.
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.
Venomancer
* Venomancer's damage-over-time abilities do little damage against Counterspell.
* Blink helps Anti-Mage get away from Venomancer's slows.
Additional:
* 
Counterspell provides magic resistance, diminishing the effectiveness of Venomancer's spells.
* Venomancer's lack of hard disable allows Anti-Mage to use 
Blink, circumventing the slows Venomancer depends on.
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
* Earthshaker's AoE stuns can save ally against Duel, forcing Legion Commander to spend Aghanim's Scepter or Black King Bar.
Venomancer
* Venomancer's slows and magical damage-over-time works well against Earthshaker's which completes lack of mobility.
* Plague Wards are useful for slowing and kitting down Earthshaker, revealing him from initiating and re-initiating and putting his Blink Dagger on cooldown if Venomancer has vision over Earthshaker.
Additional:
* Earthshaker can be kited by Venomancer's slows, which is lack of mobility.
* Plague Wards is very useful for slowing and kitting down Earthshaker, revealing him from initiating and re-initiating and putting his Blink Dagger on cooldown.
Legion Commander
* 
Untouchable makes Enchantress one of the hardest heroes for Legion Commander to Duel against, as her attack speed will be significantly slowed for the duration, even with any form of spell immunity.
* Meanwhile, when Enchantress is not a target, Enchantress can use both 
Impetus and 
Enchant on Legion Commander to help her ally win the Duel.
Venomancer
* Untouchable won't mitigate Venomancer's magical damage, and Enchantress is vulnerable to magic damage.
* Both Venomous Gale and Poison Nova lower the amount of healing received by Enchantress and her allies from Nature's Attendants.
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.
Venomancer
* Voodoo Restoration heals to counter damage over time of
Poison Nova and 
Poison Sting.
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.
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