Kunkka
* Ursa's massive physical damage can destroy Kunkka quickly.
* 
Enrage can be activated before being hit by Ghostship to prevent most of the damage.
* 
Earthshock slows Kunkka's movement speed. With no escape abilities, Kunkka is easy prey.
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
Kunkka
* 
Astral Imprisonment can allow Outworld Destroyer to save himself or allies from Kunkka's full kit.
* 
Sanity's Eclipse deal a large amount of damage, as Kunkka's mana pool is much smaller than Outworld Destroyer's.
* 
Arcane Orb deals pure damage, shredding through Kunkka and his team even with Ghostship's buff.
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.
Kunkka
* 
Supernova negates Kunkka's combo entirely, as it can't be affected by spells while using Supernova.
* 
Icarus Dive also allows Phoenix to dodge Ghostship and Torrent.
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.
Kunkka
* 
Treant Protector's 
Living Armor will also negate Tidebringer's damage.
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
Kunkka
* Similarly, they can negate your X Marks The Spot & Torrent combo by protecting your target when you use Return. Good candidates to negate your combo include Outworld Destroyer and his Astral Imprisonment, and Shadow Demon and his 
Disruption.
* Heroes with hide abilities can often dodge a Ghostship just before it hits.
* Similarly, they can negate your X Marks The Spot & Torrent combo by protecting your target when you use Return. Good candidates to negate your combo include Outworld Destroyer and his Astral Imprisonment, and Shadow Demon and his Disruption.
* A 
Eul's Scepter of Divinity can also do the trick, but, unlike the previously mentioned abilities, you can only use it on yourself and not your allies.
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
* 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
* 
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
* 
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
* 
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.
Kunkka
* 
Rage negates Kunkka's X Marks the Spot.
* As a strength hero with high strength gain and very little armor, as well as low agility gain, Kunkka is vulnerable to Lifestealer's 
Feast and 
Open Wounds.
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
* Earthshaker's AoE stuns can save ally against Duel, forcing Legion Commander to spend Aghanim's Scepter or 
Black King Bar.
Legion Commander
* 
Mystic Flare can easily burst down Legion Commander while she is Dueling.
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
* 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
Kunkka
* Timbersaw Defeats Kunkka on the center line, due to the fact that he has a huge resistance to physical damage by 
Reactive Armor, which is why 
Tidebringer almost does not break through Timbersaw, and due to 
Whirling Death Timbersaw can very much break through Kunkka and force him to leave the line, or spend money on 
Tango.
Additional:
* Timbersaw easily beats Kunkka on the midlane, due to the fact that he has huge physical damage resistance from Reactive Armor, which is why Tidebringer almost does not break through Timbersaw, and due to Whirling Death and Kunkka being a strength hero, Timbersaw can very much break through Kunkka and force him to leave the lane, or spend money on Tango.
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.
Kunkka
* 
Leap allows Mirana to easily escape Torrent and Ghostship.
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
* 
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.
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 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
* 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.
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
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
* Magnetic Field prevents Legion Commander from getting wins with Duel.
Additional:
* 
Magnetic Field prevents Legion Commander from easily gaining 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
* 
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.
Kunkka
* Heroes with cleave or multi-target attacks can quickly take on Familiars and reduce Visage's firepower like 
Gyrocopter, 
Kunkka, 
Magnus and 
Medusa.
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
* 
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.
Kunkka
* Heroes with long channeling abilities like 
Witch Doctor are easy targets for Kunkka to interrupt in team fights.
Additional:
* 
Torrent can cancel Death Ward from a far distance.
Kunkka
* Kunkka relies on his powerful AOE spells to turn the tides of teamfights. He cannot use them while silenced.
* 
Last Word can mess up Kunkka's ability synergy, silencing him in the middle of his strong combo.
* 
Global Silence can disable Kunkka's spell casting from anywhere on the map, even if Kunkka is spell immune at the time.
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
* 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.
Kunkka
* Rubick can steal abilities from Kunkka (except Tidebringer) with 
Spell Steal. Since build Aghanim's Scepter, Rubick's make two steal abilities from Kunkka when the spot is right.
Additional:
* Kunkka is a strong teamfighter with his powerful control spells, which Rubick could exploit to his advantage.
* Torrent provides another source of damage and crowd control.
* 
Ghostship is a powerful teamfight spell, providing huge magical damage to enemies and buffing allies with damage negation.
* Both skills works the best when comboed with other source of control from allies, such as Duel or 
Beserker's Call.
* 
Telekinesis can reposition an enemy onto a Torrent or Ghostship.
* 
Torrent Storm works as a disruptive spell for Rubick to create chaos around him.
* 
Tidal Wave offers another source of control and repositioning.
* As long as Kunkka gains these spells with 
Aghanim's Shard and Aghanim's Scepter, 
Rubick does not need extra items to steal these spells.
* 
X Marks the Spot serves as a utility spell for escaping, chasing and other useful functions.
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
Kunkka
* Since Tidebringer has a 4 second cooldown, Kunkka has little availability to manfight Huskar.
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
* 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
Kunkka
* X Marks the Spot breaks Flaming Lasso when used on ally and can break if used on Batrider.
Legion Commander
* Press the Attack dispels Flaming Lasso.
* Batrider is unlikely to win a Duel in any stage of the game.
Kunkka
* The slow from Torrent makes Crystal Maiden's already bad movement speed even worse.
* Kunkka has many tools to interrupt Freezing Field (most notably Torrent, Ghostship and Torrent Storm from Aghanim's Scepter), as she is an easy target while channeling it.
* It is worth noting that most of Kunkka's abilities do not pierce through spell immunity, so purchasing a Black King Bar might help Crystal Maiden in this regard.
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.
Kunkka
* Ghostship helps your team soak up damage from 
Sonic Wave and 
Scream of Pain.
* 
Queen of Pain can't escape easily from X Marks the Spot - Torrent combo.
* Outlanes Queen of Pain on the midline, due to the fact that Queen of Pain has a small reserve of health at the beginning of the game, and she suffers very much from Tidebringer, which is why she is forced to either spend money on Tango, or skip creeps and run for bounty runes, and Kunkka at this time will gain an advantage in level and gold.
Additional:
* Outlanes Queen of Pain on the midline, due to the fact that Queen of Pain has a small reserve of health at the beginning of the game, and she suffers very much from Tidebringer, which is why she is forced to either spend money on Tango, or skip creeps and run for bounty runes, and Kunkka at this time will gain an advantage in level and gold.
* Kunkka will catch her in X Marks the Spot and allow his team to kill her for stun from Torrent, because Queen of Pain has no way to avoid the cross X Marks the Spot before buying Black King Bar.
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.
Kunkka
* Windranger can't escape 
Windrun X Marks the Spot with combo Torrent or Ghostship trap.
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.
Kunkka
* X Marks the Spot prevents Broodmother from escaping.
* Tidebringer can clear Broodmother's spiders if they get in range.
Additional:
* Kunkka's entire kit is great for taking out multiple units at once.
* Tidebringer's cleave will split through a wave of spiderlings.
* X Marks the Spot is great for dragging Broodmother back out of her web for Kunkka's team to set up on her.
* Torrent and Ghostship will demolish any spiderlings within the radius.
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.
Kunkka
* 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.
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.
Kunkka
* Heroes with strong area-of-effect damage can make quick work of Chen's converted creeps and at same time gain farm: Magnus, 
Jakiro, 
Shadow Fiend, Kunkka, 
Luna, 
Dragon Knight, Medusa, 
Alchemist.
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.
Kunkka
* Tidebringer, Torrent and Ghostship destroys Chaos Knight's 
Phantasm army all through the game.
Legion Commander
* Heroes with strong area damage to destroy Phantasm illusions: Axe, 
Ember Spirit, Legion Commander, Phoenix
Kunkka
* Tidebringer's cleave will cripple any of his summons.
* Could potentially build Heaven's Halberd to cripple Lycan even more.
Additional:
* Tidebringer can be used to kill Lycan's summons.
* Can also build into 
Heaven's Halberd which will disable Lycan's auto attacks, crippling him even more.
Legion Commander
* Heroes who rely on summons will see them destroyed easily by Overwhelming Odds: Lycan, Arc Warden, Warlock, Chen
Kunkka
* Kunkka can bring Anti-Mage back with X Marks the Spot, effectively negating Blink or forcing him to wait out the debuff before Blinking.
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.
Kunkka
* Ghostship helps your team soak up damage from 
Chaotic Offering and hit summons hard.
* Tidebringer clears summons later in the game.
* Most of your spells can interrupt 
Upheaval.
Legion Commander
* Heroes who rely on summons will see them destroyed easily by Overwhelming Odds: Lycan, Arc Warden, Warlock, Chen
Kunkka
* In general, highly mobile heroes like 
Earth Spirit or 
Storm Spirit are at a disadvantage against X Marks the Spot.
* Similarly, heroes with low cooldown teleports can be afraid to split push against X Marks the Spot, such as 
Tinker and Nature's Prophet.
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
* Duel's long duration prevents Terrorblade from swapping his health with 
Sunder.
* Overwhelming Odds deals high damage to Terrorblade's illusions.
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.
Kunkka
* Spectre can't escape with 
Spectral Dagger under X Marks the Spot.
* Kunkka can dominate Spectre's lane using Tidebringer and gain an advantage.
* Ghostship helps your team soak up damage from 
Haunt.
Kunkka
* Ghostship can stun Faceless Void and give damage reduction to allies that are trapped during Chronosphere.
* Torrent can stun Faceless Void from outside Chronosphere.
* X Marks the Spot can bring back Faceless Void if he escapes using Time Walk.
* If the timing is right and there are allies to attack, a combination of X Marks the Spot, Ghostship, Torrent and Tidebringer can kill Faceless Void instantly.
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
* 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
* Duel's long duration prevents Nyx Assassin escaping from 
Vendetta. With Aghanim's Scepter, she can also bypass 
Spiked Carapace.
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.
Kunkka
* Tidebringer will deal lots of damage to Alchemist before he builds physical survivability items.
* Torrent and X Marks the Spot can control Alchemist at all stages of the game before he has Black King Bar.
* Ghostship's rum buff will greatly reduce the Alchemist's damage output in teamfights including his Radiance.
Kunkka
* X Marks the Spot negates Stampede.
Kunkka
* Ghostship helps your team soak up damage from 
Epicenter, especially if he initiates during the battle.
* 
Sand King can't dodge X Marks the Spot - Torrent combo by his abilities. Torrent drags him out of his 
Sand Storm
Kunkka
* X Marks the Spot prevents Dark Seer or his allies from escaping with Surge.
Kunkka
* Using X Marks the spot Kunkka can prevent Ember Spirit from escaping with Activate Fire Remnant, until he purchase Eul's Scepter of Divinity or Linken's Sphere.
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
Kunkka
* Similarly, heroes with low cooldown teleports can be afraid to split push against X Marks the Spot, such as Tinker and Nature's Prophet.
* In general, highly mobile heroes like Earth Spirit or Storm Spirit are at a disadvantage against X Marks the Spot.
* Similarly, heroes with low cooldown teleports can be afraid to split push against X Marks the Spot, such as Tinker and Nature's Prophet.
Additional:
* X Marks the Spot can be used to prevent Tinker from escape with Blink Dagger or 
Keen Conveyance, discourage him from snapping farm and snapping gank. However, in later game, it'll be much more difficult because Tinker can buy Black King Bar or Linken's Sphere to prevent Kunkka from placing X on him, or Eul's Scepter of Divinity to prevent the recall.
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
* 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.
Legion Commander
* Invoker's spells will disable and destroy Legion Commander while she's locked in a Duel.
Kunkka
* Tidebringer pressures Invoker easily in lane due to Invoker's low health and armor in the early game.
Legion Commander
* Heroes with long lockdowns: 
Shadow Shaman, Legion Commander.
Kunkka
* Heroes that can negate Hoodwink's mobility: Kunkka, 
Disruptor, 
Mars.
Kunkka
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: 
Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, 
Elder Titan, Faceless Void, Rubick, Keeper of the Light, 
Pugna, Invoker, 
Spectre, Alchemist, Treant Protector, 
Lina, Oracle, Zeus, Shadow Shaman, Phoenix, 
Razor, 
Huskar, 
Batrider, Kunkka, 
Tidehunter, Wraith King, Sand King, Medusa, 
Dawnbreaker.
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
Kunkka
* Similarly, heroes with low cooldown teleports can be afraid to split push against X Marks the Spot, such as Tinker and Nature's Prophet.
* In general, highly mobile heroes like Earth Spirit or Storm Spirit are at a disadvantage against X Marks the Spot.
* Similarly, heroes with low cooldown teleports can be afraid to split push against X Marks the Spot, such as Tinker and Nature's Prophet.
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.
Kunkka
* Heroes who are strong against mobile heroes: Disruptor, 
Bloodseeker, Kunkka, Keeper of the Light.
Legion Commander
* Heroes with long or multiple disables will prevent Legion Commander from winning Duels: Shadow Shaman, Lion
Kunkka
* Lion lacks mobility or escape mechanisms, making him an easy target for abilities like 
Mirana's 
Sacred Arrow or 
Leshrac's 
Split Earth, or combos like Kunkka's X Marks the Spot into Torrent.
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.
Kunkka
* In general, highly mobile heroes like Earth Spirit or Storm Spirit are at a disadvantage against X Marks the Spot.
* Similarly, heroes with low cooldown teleports can be afraid to split push against X Marks the Spot, such as Tinker and Nature's Prophet.
Kunkka
* Heroes that punish mobile heroes: Bloodseeker, Keeper of the Light, Kunkka, Disruptor.
Kunkka
* X Marks the Spot is a counter to Disruptor's 
Glimpse, but you need quick reactions to pull it off.
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
* Heroes rely on their debuff to control the opponent will have a hard time against Press the Attack: Venomancer, Earth Spirit, Ogre Magi
Kunkka
* Heroes that can keep Marci for a long time in one place so she can't pursue her targets, like Bane, Lion, Shadow Shaman, Invoker, Disruptor and Kunkka.
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.
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
* 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.
Kunkka
* Melee heroes with low mobility can be kited and killed by Viper: Treant Protector, Kunkka, Alchemist, Troll Warlord, Wraith King, 
Tiny, Sven.
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
* 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.
Kunkka
* Kunkka's Ghostship and Torrent disrupt fights in 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.
Kunkka
* With his 
Take Aim, Sniper can simply sit out of your ability range and deal massive damage if not killed first.
* 
Assassinate can target allies who are still alive with low health because of Ghostship's buff.
* 
Headshot makes it harder for Kunkka to position/escape and makes it hard for Kunkka to hit with Tidebringer.
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.
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
Kunkka
* Heroes with long range abilities are also able to touch Zeus, such as 
Clockwerk, Kunkka, Puck, 
Skywrath Mage, Spirit Breaker, Tusk and others.
Kunkka
* Blade Fury negates Kunkka's X Marks the Spot.
* Kunkka has no way to dodge 
Omnislash.
* Kunkka has no way to hit 
Healing Ward directly in battle, and it mitigates Ghostship and Tidebringer's damage.
Legion Commander
* Duel pierces spell immunity and forces him to attack Legion Commander, making him unable to use Omnislash.
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
* 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.
Kunkka
* X Marks the Spot is good to prevent a single meepo from escaping from a deadly situation.
* Tidebringer, Torrent and Ghostship destroys Meepo's clones.
Additional:
* Tidebringer's cleave damage can wear down Meepo's clones quickly. It can also give Meepo problems in the lane, due to his melee range and initially low health pool.
* Ghostship and Torrent can effectively disable Meepo while dealing heavy damage.
* X Marks the Spot prevents attempts to escape using Poof.
Kunkka
* Clinkz's high damage output and insane attack speed late-game can take Kunkka out of the fight before it begins.
* 
Burning Barrage and 
Searing Arrows together can kill allies easily even under Ghostship's buff.
* 
Skeleton Walk can allow Clinkz to make a quick escape after Kunkka's combo, or even avoid it all together.
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
* 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
* 
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.
Kunkka
* X Marks the Spot will return Underlord or his teammate if they escape with Fiend's Gate.
* Torrent, Ghostship, Torrent Storm from Aghanim's Scepter and Tidal Wave from Aghanim's Shard are all excellent abilities for intercepting Underlord and his team if Underlord chooses to travel to the designated point of the map with Fiend's Gate.
Kunkka
*
Guardian Angel makes allies immune to all physical damage, effectively causing Tidebringer to do no damage.
Purification is a powerful, pure damaging heal that can save Omniknight's allies after Kunkka's large damage.
*
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.
Duel.
*
Additional:
* Both Guardian Angel and Purification are perfect counters against