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.
Oracle
* 
Disruption can protect Shadow Demon's allies from Fortune's End, preserving healing or buffs. It can also catch Oracle's allies, allowing 
Shadow Poison to be used without being dispelled.
* 
Demonic Purge prevents over-time healing during False Promise, such as Purifying Flames and 
Urn of Shadows. If he has Aghanim's Scepter, this issue can persist for longer or on multiple allies.
* It will not, however, prevent healing from instant abilities, items, or auras, making 
Mekansm a good choice against him.
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
* 
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
* 
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
* 
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.
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
* 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.
Legion Commander
* Solar Guardian can save allies who are being dueled and will interrupt her Duel initiation.
Oracle
* Oracle's burst damage is ineffective against 
Dispersion.
* Disarm provided by Fate's Edict is not as significant debilitation for Spectre as it might be for other carries since She can do damage even without landing attacks.
Additional:
* Oracle's burst damage is not enough to take down Spectre due to Dispersion.
* Disarm from 
Fate's Edict does not hinder Spectre that much, since she can deal damage even without landing a single attack.
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.
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
* 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
Oracle
* 
Elder Titan's 
Echo Stomp can turn into a 5 second stun on an ally under the effect of False Promise, as it delays all damage and makes it impossible to break the damage threshold of Echo Stomp.
Oracle
* Heroes with long disables, like 
Lion, 
Night Stalker, or Legion Commander, can prevent Oracle from using spells or items.
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.
Oracle
* Heroes who are not easily crippled by Fate's Edict or Fortune's End, such as 
Timbersaw, or those who can dispel them, such as 
Phantom Lancer, can kill Oracle unhindered.
Legion Commander
* Heroes with 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
Oracle
* Because Oracle uses few, powerful instances of damage to kill enemies, 
Templar Assassin's 
Refraction and 
Visage's 
Gravekeeper's Cloak can absorb his burst damage.
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.
Oracle
* Heroes with the ability to heal allies will not be able to heal heroes affected by 
Doom: 
Chen, 
Dazzle, 
Io, 
Oracle, 
Omniknight, 
Witch Doctor, 
Winter Wyvern, 
Abaddon, etc.
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
* 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
* 
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.
Oracle
* 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.
Oracle
* False Promise will not save an ally from 
Culling Blade if their health is low enough.
* Fate's Edict, offensively or defensively, does little to protect Oracle's allies from the majority of Axe's damage.
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
* 
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.
Oracle
* Fate's Edict cripples many heroes who rely on attacks, such as 
Phantom Assassin, 
Sven, or 
Enchantress, without a dispel or a Black King Bar.
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.
Oracle
* Fortune's End can catch out or impair position-based heroes with low mobility, such as 
Sniper or Razor.
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.
Oracle
* 
Time Walk and 
Backtrack allow Faceless Void to easily negate Oracle's burst damage.
* 
Time Dilation is effective against Oracle's low-cooldown spells. Although dispellable with Fortune's End, it can still catch Oracle off guard if Fortune's End is on cooldown.
* However, False Promise is one of the best abilities in the game to delay or even potentially save any ally caught in 
Chronosphere. Combined with Fate's Edict, a well-positioned Oracle denies Faceless Void and his team from attempts at solo-Chronosphering key targets to open up a teamfight.
Oracle
* Any hero that can nullify effects of Chronosphere: (
Keeper of the Light with Aghanim's Scepter during daytime, Winter Wyvern), banishing him or Faceless Void (Outworld Destroyer, Shadow Demon, 
Earth Spirit with Aghanim's Scepter) or protecting him in other ways (Dazzle, Oracle, Abaddon) can greatly limit Chronosphere's potential.
Legion Commander
* Invoker's spells will disable and destroy Legion Commander while she's locked in a Duel.
Legion Commander
* Heroes with long lockdowns: 
Shadow Shaman, Legion Commander.
Legion Commander
* Song of the Siren lasts long enough to prevent a successful Duel (but only if Naga wasn't the target).
Legion Commander
* Heroes who rely on illusions will see them destroyed easily by Overwhelming Odds: Phantom Lancer, 
Chaos Knight, 
Terrorblade, Naga Siren
Legion Commander
* Press the Attack dispels Flaming Lasso.
* Batrider is unlikely to win a Duel in any stage of the game.
Oracle
* 
False Promise dispels Flaming Lasso.
* Fortune's End can root Batrider after he uses Flaming Lasso. It can also dispel Sticky Napalm and Flamebreak.
* Fate's Edict when used on a Lasso'd target will leave them immune to magical damage, making it difficult to burst them quickly before the Lasso ends.
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
Oracle
* Oracle can negate all of Techies' skills with Fate's Edict, as they are all magic damage. Fate's Edict can also be used to search and trigger 
Proximity Mines when crossing mined territory.
* Oracle can dispel 
Reactive Tazer off Techies, as well as the silence from 
Blast Off!, with Fortune's End.
* Oracle can further delay Techies' burst damage capability with False Promise.
Additional:
* Fate's Edict gives 100% magic resistance, which prevents most of Techies' damage.
* Oracle's Fortune's End dispels Reactive Tazer buff from Techies allowing him to be attacked. However, Reactive Tazer will instantly perform the area of effect disarm that is normally applied at the end of the duration.
* Fortune's End will also dispel Blast Off silence, Techies' Etheral Blade, Proximity Mines' magic resistance reduction, and Sticky Bomb's slow. However beware that it will only dispel Sticky Bomb's first or second instance of slow and not the damage, which will trigger as normal.
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.
Oracle
* Fortune's End can catch out or impair position-based heroes with low mobility, such as Sniper or Razor.
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.
Oracle
* Heroes with little health or magic resistance are easily picked off with Oracle's magic burst, such as 
Skywrath Mage, Crystal Maiden, or Enchantress.
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
Oracle
* Oracle's high magic damage output can easily take down Rubick's low health pool.
* Because Oracle can combo spells in rapid succession (due to low cooldowns), it may be difficult for Rubick to 
Spell Steal False Promise. This scenario can even be avoided by shift queueing Fortune's End and casting it immediately, as it has no cast point, or by staying in the back line of fights if out of mana.
* As a position based hero, Rubick will have a very hard time against Fortune's End due to its absurd range and very long root duration.
Legion Commander
* Duel pierces spell immunity and forces him to attack Legion Commander, making him unable to use 
Omnislash.
Oracle
* Heroes with abilities that can save teammates are also effective such as Shadow Demon, Dazzle, Oracle, 
Bane, 
Pugna, Tusk, Winter Wyvern, Io, 
Underlord, Treant Protector and Keeper of the Light.
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
Oracle
* Fate's Edict gives full immunity from Ogre Magi's mostly magical damage.
* Fortune's End can dispel Ignite (when used on allies) and Bloodlust (when used on enemies).
* False Promise can dispel Ignite and Fireblast.
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.
Oracle
* Fortune's End and False Promise easily dispel many crippling debuffs, such as Venomancer's 
Venomous Gale, or Skywrath Mage's 
Ancient Seal.
Additional:
* 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
* 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.
Oracle
* Heroes that can purge his slow and disables are very difficult to go on and their team: Abaddon, Oracle.
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.
Oracle
* Oracle with Fortune's End and False Promise
* 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.
Oracle
* False Promise effectively nullifies Primal Roar's single-target initiation on allies.
* 
Purifying Flames kills Beastmaster's Hawk instantly and Boar with two casts.
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.
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
* 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.
Oracle
* Heroes with dispels: Legion Commander, Oracle, Slark, Phantom Lancer
Oracle
* During the laning stage, Oracle's Purifying Flames nullifies any damage that Heartstopper Aura might inflict.
* Fate's Edict and False Promise can protect an ally from Reaper's Scythe.
* Oracle can dispel Ghost Shroud with Fortune's End.
Additional:
* Fortune's End can dispel 
Ghost Shroud, negating the skill's utility. Also it's worth noting that Necrophos takes additional magic damage when in Ethereal state, which makes Purifying Flames a powerful nuke against him.
* Fate's Edict fully negates the damage from 
Reaper's Scythe, which its own delayed animation makes it relatively easy to predict and nullify.
Oracle
* Oracle can negate and shut down Primal Beast simply with Fate's Edict, especially in the early game, as a majority of his damage-dealing spells are magic.
* Oracle can interrupt Primal Beast's 
Onslaught charge with a well-timed Fortune's End.
* Primal Beast's lethal burst damage combos can be further stalled with False Promise; combined with Fate's Edict and regen from Purifying Flames, Oracle can even completely negate Primal Beast's offense.
Additional:
* Fate's Edict completely negates all of Primal Beast's major damage-dealing spells in the early game and can render Primal Beast useless when cast on a target he is focusing, or in Oracle's defense against Primal Beast himself.
* Fortune's End keeps Primal Beast in place, especially while trampling or in the middle of an Onslaught charge.
* False Promise can interrupt Primal Beast's abilities, as well as further delay Primal Beast from dealing lethal burst damage. In combination with Fortune's End, Oracle can potentially save an ally from Primal Beast's spell combos.
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
* 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.
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.
Oracle
* Fate's Edict allows Oracle to make allies spell immune, allowing him to save allies from Jakiro's spells.
* Fate's Edict can be cast onto Jakiro to disarm him and prevent him from pushing with his Liquid Fire.
* False Promise allows Oracle to free allies from Jakiro's Ice Path.
Legion Commander
* Duel's long duration prevents Nyx Assassin escaping from 
Vendetta. With Aghanim's Scepter, she can also bypass 
Spiked Carapace.
Oracle
* Fortune's End not being disjointable is almost an ensured disable if Dark Willow tries to escape with Shadow Realm. Dispels Cursed Crown and Terrorize.
* Fate's Edict negates all her magic damage in case she catches a single hero.
* False Promise's strong dispel removes Dark Willow's disables.
Additional:
* Fortune's End can easily dispel 
Cursed Crown before it times out and stuns. He can also save a stunned ally with False Promise.
* Fate's Edict can easily negate 
Bedlam's over-time damage, since the spell provides no form of control. Similarly, he can also negate the magic burst from 
Shadow Realm.
* Fortune's End can dispel the fear effect from 
Terrorize, and it can remove the root from Bramble Maze if cast quick enough. Be mindful that Fortune's End only dispels your allies' debuffs on the primary target.
Oracle
* Oracle's Fate's Edict will protect an ally from Leshrac's nuking damage.
* Oracle's False Promise can dispel Leshrac's stun and slow from his abilities, allowing an ally to escape.
* Fortune's End can stop Leshrac from chasing opponents or running away.
Legion Commander
* Duel's long duration prevents Weaver from activating Time Lapse or escaping with 
Shukuchi.
Legion Commander
* Duel is a great initiation to kill Death Prophet before she can cast Exorcism. Furthermore, Legion Commander often builds Blade Mail and can reflect Exorcism's damage to kill Death Prophet easily.
Legion Commander
* 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.
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.
Oracle
* Fortune's End dispells Marci's 
Sidekick, removing additional damage and lifesteal.
* Fate's Edict disarms Marci, preventing her from attacking with 
Unleash. Also it is useful against Marci or her ally affected by Sidekick.
* False Promise is a great tool to save an ally focused by Marci.
Oracle
* Fortune's End dispels Ion Shell and Surge, making any gank attempt on Dark Seer in the laning phase likely to succeed.
* Fate's Edict prevents all magical damage that comes from Dark Seer's abilities.
* Fortune's End dispels Ion Shell on creeps, which Dark Seer relies on to farm and zone.
Additional:
* Fortune's End can dispel 
Ion Shell, a skill that helps Dark Seer immensely in the laning phase, as well as 
Surge, a move-speed buff, effectively allowing Oracle to control Dark Seer, especially in the laning phase.
Oracle
* Oracle can shut down both of Ember's early game abilities. Fortune's End can dispel 
Flame Guard on Ember Spirit and 
Searing Chains on allies.
* When Ember Spirit is affected by Fortune's End, his 
Fire Remnants move at 0 movement speed.
* Disarming him with Fate's Edict does affect Ember's Sleight of Fist ability, possibly making him useless for a few seconds in the late game without a dispel or spell immunity. This is especially good if he has a rapier or two. However, positioning for this is difficult when Ember plays far back.
Oracle
* Heroes with little health or magic resistance are easily picked off with Oracle's magic burst, such as Skywrath Mage, Crystal Maiden, or Enchantress.
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.
Oracle
* 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.
Oracle
* 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 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
* 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.
Oracle
* Oracle's reliance on spamming his spells can be easily hindered by Silencer's Arcane Curse.
* Last Word and Global Silence negates Oracle's attempt to save his allies with his spells.
* Fate's Edict is useless against Glaives of Wisdom's pure damage.
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.
Oracle
* Fortune's End can nullify 
Arcane Curse, 
Last Word, and 
Global Silence, if cast at the right time with the right targets.
* Fate's Edict can prevent Silencer from attacking, which he relies on with 
Glaives of Wisdom, for a lot of his damage.
Oracle
* Fate's Edict cripples many heroes who rely on attacks, such as Phantom Assassin, Sven, or Enchantress, without a dispel or a Black King Bar.
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
Oracle
* Anti-Mage can withstand magical burst damage much better than other carries, making him effective against nukers: Lich, 
Necrophos, Oracle, and 
Leshrac.
Additional:
* Oracle has minimal damage potential against Anti-Mage due to 
Counterspell, and may even have some ability damage reflected at himself.
* Anti-Mage can easily overwhelm Oracle with 
Mana Break and 
Mana Void.
* 
Blink allows Anti-Mage to easily chase and take advantage of Oracle's low mobility.
Legion Commander
* Duel renders Anti-Mage's escape capabilities with Blink and Counterspell useless. Blade Mail and Moment of Courage work well against Anti-Mage's relatively low health.
* A good initiation from Legion Commander and her team is enough to effortlessly kill Anti-Mage.
Additional:
* Counterspell offer no protection against Duel at all.
* Duel locks down Anti-Mage for a long duration, preventing him from escaping with Blink. One successful Duel initiation is usually enough for Legion Commander's team to kill Anti-Mage.
Legion Commander
* Heroes with abilities that blind or cause Legion Commander to miss will prevent her from winning Duels: Arc Warden, Keeper of the Light, Riki, Tinker
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
* Troll Warlord's melee bash and high attack speed can often help him and his allies win Duels against Legion Commander.
Oracle
* Fate's Edict can disarm Troll, rendering him useless in a teamfight, especially if he has already used Battle Trance.
* Fortune's End and Purifying Flames can provide ample magic damage to help burst down Troll Warlord quickly in the early to mid game.
* False Promise can save an ally from Troll Warlord's initiation, forcing him to switch targets and lose his Fervor stacks, or waste time during Battle Trance.
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.
Oracle
* Phoenix does significant magic damage over time which can either be dispelled or negated by Fate's Edict.
* Oracle's burst damage potential can prove lethal to Phoenix, as they already have to sacrifice health to cast their basic skills.
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
Oracle
* False Promise can dispel the stun from Cold Feet and can save an ally that's about to shatter from Ice Blast, even allowing healing with Purifying Flames by delaying it until after the debuff expires.
* Purifying Flames allows Oracle to deny his allies if they're affected by Ice Blast. If he brings his allies' health to or below the shatter threshold, it will count as him denying the ally. However, this does not work on Oracle himself.
* Fate's Edict provides 100% magic resistance, making it good against all of Ancient Apparition's abilities at all stages of the game.
* Fortune's End can dispel Cold Feet from allies.
Additional:
* False Promise can prevent the shatter from Ice Blast and Fate's Edict can protect an ally from the magical damage over time for a while.
* Oracle can deny allies who are frostbitten. If he uses Purifying Flames to reach the shatter threshold, it will count as a deny.
* Fortune's End can dispel 
Cold Feet on affected allies, preventing them from getting frozen.
Oracle
* Heroes who can take advantage of Oracle's low mobility or catch him out of position, such as 
Clinkz and 
Anti-Mage, can easily pick him off.
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.
Oracle
* Oracle cannot easily deal with swarms of units, making him weak against heroes like Phantom Lancer or Broodmother.
Legion Commander
* Overwhelming Odds's damage stacks with each enemy unit in its radius. If this hits Broodmother and a large number of spiders it can deal significant amounts of damage.
* Moment of Courage has a high chance to proc if Broodmother and all of her spiders are attacking her.
* Duel can keep Broodmother in place long enough for Legion's team to kill her.
Additional:
* Overwhelming Odds is great at killing many stacked up spiderlings, thus giving Legion Commander a large buff.
* Duel is a reliable way to lock down Broodmother, preventing her from running into the treeline.
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
* 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.
Oracle
* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.
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.
Oracle
* Heroes with strong dispels can dispel Bane's disables from their allies: Oracle, Legion Commander, Omniknight.
Oracle
* Heroes who are not easily crippled by Fate's Edict or Fortune's End, such as Timbersaw, or those who can dispel them, such as Phantom Lancer, can kill Oracle unhindered.
Legion Commander
* Heroes 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.
Oracle
* Fortune's End cannot dispel 
Warpath stacks on Bristleback or 
Quill Spray stacks on allies.
* 
Bristleback can heavily reduce Oracle's damage output. With it, Oracle may accidentally heal Bristleback with Purifying Flames, especially if Bristleback has bonus magic resistance.
Legion Commander
* Duel makes Bristleback fight Legion Commander face to face, forcing him to take full damage.
* Press the Attack dispels the slow from stacks of Viscous Nasal Goo.
Additional:
* When dueled, Bristleback will have to face Legion head on, not allowing his passive Bristleback to come into effect.
Legion Commander
* Heroes with global abilities can give Legion Commander's opponent an edge in Duels from anywhere on the map: Nature's Prophet, Ancient Apparition, Zeus, Invoker, Treant Protector
Legion Commander
* Legion Commander's Overwhelming Odds deals damage for every Treant it hits, which allows it to easily wipe out large waves of them.
Legion Commander
* Heroes with long or multiple disables will prevent Legion Commander from winning Duels: Shadow Shaman, Lion
Oracle
* Heroes with long disables, like Lion, Night Stalker, or Legion Commander, can prevent Oracle from using spells or items.
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.
Oracle
* 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
* 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.
Oracle
* Fortune's End applies a basic dispel which can be used to dispel Corrosive Haze, or even Slardar's own Guardian Sprint.
* False Promise is able to dispel Corrosive Haze and Slithereen Crush stun/slow from any allies Oracle chooses to cast it on.
* Fate's Edict can also be cast on Slardar to prevent him from proccing his Bash of the Deep.
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
Oracle
* All of Pugna's damage is magical, which can get blocked by Fate's Edict's 100% magic resistance.
* Oracle has two abilities that apply a dispel, which can easily remove Decrepify on his ally or Oracle.
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.
Oracle
* It is especially easy for Oracle to negate the damage from Maledict, and even heal through it with Fate's Edict and Purifying Flames.
* If by some miracle an enemy is still about to die because of Maledict, he can still save him with False Promise.
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
* 
Mystic Flare can easily burst down Legion Commander while she is Dueling.
Oracle
* Fate Edict can completely negate Skywrath Mage's heavy magic damage.
* Fortune End dispels Ancient Seal.
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
* 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".
Oracle
* Heroes with area dispel can kill multiple skeletons at once: 
Brewmaster, Oracle.
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.
Oracle
* Fortune's End's AoE dispel will remove Heavenly Grace and Guardian Angel.
Additional:
* Oracle can dispel Heavenly Grace (which he can also bait out with Fate's Edict).
* With Fortune's End, Oracle can dispel Guardian Angel in an area of effect.
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.
Oracle
* Because Oracle uses few, powerful instances of damage to kill enemies,
Templar Assassin's 
Refraction and 
Visage's 
Gravekeeper's Cloak can absorb his burst damage.