* Atrophy Aura's percentage-based damage reduction greatly diminishes Legion Commander's overall damage output, even if she has won many Duels.
* Dark Rift can be used to save Underlord or his allies from Duels if properly timed.
Additional:
* Atrophy Aura makes it hard for Legion Commander to win Duels.
* Dark Rift can be used to save Underlord and his allies from a Duel.

* Pit of Malice can be cast in the path of Spirit Breaker's Charge of Darkness to cancel it.
* Dark Rift provides a way to escape from a gank for Underlord and his teammates.

* 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.

* Clockwerk can use Power Cogs to repel Spirit Breaker when he charges in with Charge of Darkness.
* Spirit Breaker's slow 0.6 second attack animation attacks do little damage against Clockwerk. It can also constantly be interrupted by Battery Assault.
* Nether Strike's 1.2 second charge time gives Clockwerk plenty of time to activate Blade Mail and for Battery Assault to cancel it.
Additional:
* Battery Assault will continuously prevent Spirit Breaker from using Nether Strike, Charge of Darkness and even right clicking because of his long attack animation.
* Charge of Darkness can be cancelled by a correctly timed Hookshot.
* Should Clockwerk or his allies be targeted by Charge of Darkness, he can stop it by casting Power Cogs in Spirit Breaker's path or around the target.

* 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.

* In the early game, Omniknight can look like an easy target for Spirit Breaker, but with Purification and Degen Aura, what could be an opportunity could quickly turn into disaster.
* Heavenly Grace can be used to counter Charge of Darkness by minimizing the damage and lowering the stun duration with status resistance.
* Spirit Breaker's Greater Bash from all sources (Charge of Darkness or normal attacks) deals lesser damage if he is within the radius of Degen Aura.
* Due to this, Spirit Breaker's damage will always be lower when targeting Omniknight.

* 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 on.
* 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.

* Nether Strike can't remove Static Link and reduces Spirit Breaker's physical damage output.
* Eye of the Storm melts Spirit Breaker's armor, and makes him much less tanky.
Additional:
* Static Link drains damage bonus from Greater Bash, it cannot be removed by Nether Strike.
* Eye of the Storm melts Spirit Breaker's armor, and makes him much less tanky.

* Earthshaker's AoE stuns can save ally against Duel, forcing Legion Commander to spend Aghanim's Scepter or Black King Bar.

* Fissure interrupts Spirit Breaker during Charge of Darkness.

* If Medusa activates Stone Gaze, the charge will inevitably fail.
* Mana Shield and overall tankiness allows Medusa to easily survive Spirit Breaker's initiation.

* Mana Shield makes Medusa very hard to take down in Duels.
* Stone Gaze stops Legion Commander from Dueling altogether, regardless of who she targets.

* Spirit Breaker's slow attack speed and moderate damage do very little to harm Dragon Knight, even if ganked with Charge of Darkness.

* Dragon Knight's high natural sustain and health regeneration from Dragon Blood makes him hard to take down in Duels.

* Spirit Breaker's slow attacks cannot harm a hero shielded by Living Armor.
Additional:
* Living Armor can mitigate a large portion of Spirit Breaker's damage since his attacks are slow.
* Treant Protector can also counter initiate Spirit Breaker with Leech Seed and his bash from Nature's Guise before he manages to escape.

* Clinkz, Sniper, Lone Druid, Troll Warlord, Legion Commander, Wraith King and others are some of the Heroes that bases themselves on attacks with little or no spell power, suffering in the grassy hands of Overgrowth.

Additional:
* Living Armor's global range makes it nearly impossible for Legion Commander to win Duels in the early to mid-game.

* Heroes who continue dealing damage while being stunned: Luna, Razor, Axe, Bristleback, Leshrac,

* Provided Luna is able to cast it in time, Eclipse can help win a Duel from Legion Commander.
* If Luna isn't the target, she can easily use Lucent Beam and Eclipse to win the fight for the ally.
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 players will always have a Black King Bar or Aghanim's Scepter handy since both abilities do not pierce through spell immunity.

* Heroes who can hide the Dueled target (Outworld Devourer, 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.

* Due to Spirit Breaker's low attack speed, Supernova is problematic for Spirit Breaker to take down, and even more so with Fire Spirits debuff applied.
* Icarus Dive grants Phoenix capability to quickly escape to safety.

* 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.

* Heroes that can slow Charge of Darkness by a huge amount: Venomancer, Viper, Dazzle, Arc Warden

* Heroes who can hide the Dueled target (Outworld Devourer, Shadow Demon, Tusk, Phoenix with Aghanim's Scepter etc).

Additional:
* Outworld Devourer 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.

* Astral Imprisonment can be used to protect allies by imprisoning either them or Spirit Breaker.
* Arcane Orb will heavily drain Spirit Breaker's intelligence, rendering him almost useless and unable to cast spells. Spirit Breaker's low intelligence also means Sanity's Eclipse will deal a lot of damage to him.

* 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.

* Earthbind's root prevents/interrupts Charge of Darkness.
* As a single target focused hero without much damage output, Spirit Breaker is ineffective in general against Meepo. Consider upgrading Nether Strike with Aghanim's Scepter to spam AoE stuns against Meepo clones.
Additional:
* Spirit Breaker heavily relies on disabling one enemy at a time therefore rendering him useless against five Meepos at once.

* 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.

* Durable heroes: Axe, Bristleback, Tidehunter, Wraith King

* Malefice prevents Spirit Breaker from using his spells for the duration.
* Demonic Conversion's eidolons have high magic resistance, receiving little damage from Charge of Darkness.

* Due to Spirit Breaker's low attack speed, Tombstone is problematic for Spirit Breaker.
* The zombies summoned from Tombstone apply a stacking movement speed slow, which can significantly reduce Greater Bash's damage.
* Soul Rip and Decay allows Undying and his allies to survive from incoming ganks of Spirit Breaker.

* Bramble Maze stops Charge of Darkness in its tracks. Its very long duration means it can be used as an obstacle to block off an incoming Spirit Break during teamfights.
* Shadow Realm and Bedlam can be activated when Dark Willow sees Charge of Darkness coming, preventing Spirit Breaker from using Nether Strike after the initial stun.

* 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.

* 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.

* God's Strength with Sven's tankiness and item build makes him difficult to take down in Duels.
* Storm Hammer can be used to interrupt Duels (until Legion Commander buys Aghanim's Scepter).
* Sven also has a talent at level 15 that allows Storm Hammer to apply a basic dispel on any enemies hit by it, which can remove the buffs from Overwhelming Odds and Press the Attack.
* Warcry gives a shield to Sven's teammates, which can completely waste Duel's duration depending on how much strength Sven has.

* 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

* Mystic Flare can easily burst down Legion Commander while she is Dueling.

* Cold Snap allows Invoker to interrupt Charge of Darkness and Nether Strike.
* Tornado's long range can be used to cancel Charge of Darkness.
* Deafening Blast prevents Spirit Breaker from right clicking and thus proccing his Greater Bash.

* 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

Additional:
* Invoker's spells will disable and destroy Legion Commander while she's locked in a Duel.

* 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.

* 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.

* 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.

* Searing Chains can stop Charge of Darkness if timed correctly.
* Activate Fire Remnant can be used to escape an approaching Spirit Breaker, or lead Spirit Breaker into a bad situation.
* Activate Fire Remnant and Sleight of Fist allows Ember Spirit to dodge Charge of Darkness if timed correctly.

* Heroes with fast movement abilities will suffer huge damage when afflicted by Rupture: Spirit Breaker, Earth Spirit, Dark Seer.

* Heroes that can slow Charge of Darkness by a huge amount: Venomancer, Viper, Dazzle, Arc Warden

* Heroes with abilities that blind or cause Legion Commander to miss will prevent her from winning Duels: Arc Warden, Keeper of the Light, Riki

Additional:
* Magnetic Field prevents Legion Commander from getting wins with Duel.

* Heroes that have a weak laning stage: Spectre, Nyx Assassin, Clockwerk, Spirit Breaker, Omniknight, Pudge.

* Heroes that usually builds Linken's Sphere as a core item: Weaver, Medusa, Morphling, Queen of Pain, Storm Spirit

* Durable heroes: Axe, Bristleback, Tidehunter, Wraith King

* Heroes that can slow Charge of Darkness by a huge amount: Venomancer, Viper, Dazzle, Arc Warden

* Troll Warlord's melee bash and high attack speed can often help him and his allies win Duels against Legion Commander.

* Heroes who continue dealing damage while being stunned: Luna, Razor, Axe, Bristleback, Leshrac,

* Heroes who continue dealing damage while being stunned: Luna, Razor, Axe, Bristleback, Leshrac,

* Mana Drain has an extremely long range and low cooldown. It can easily deplete most heroes of their entire mana pools, especially those with smaller mana pools such as Tiny or Spirit Breaker.

* Heroes with long or multiple disables will prevent Legion Commander from winning Duels: Shadow Shaman, Lion

* Legion Commander is unlikely to win a Duel against Ursa.

Additional:
* 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.
* Fury Swipes can give Ursa the edge in Duels.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* Heroes that usually builds Linken's Sphere as a core item: Weaver, Medusa, Morphling, Queen of Pain, Storm Spirit

* Heroes who can hide the Dueled target (Outworld Devourer, 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.

* Heroes with ways to protect themselves or allies from Spirit Breaker's initiation: Shadow Demon

* Enfeeble, Nightmare and Fiend's Grip all prevent Legion Commander from winning Duels, especially when Bane has Blink Dagger.
Additional:
* 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.

* 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.

* Heroes with long or multiple disables will prevent Legion Commander from winning Duels: Shadow Shaman, Lion

* Can easily interrupt and disable Spirit Breaker with hex if being charged.

* Because Duel requires both combatants to face each other, Bulwark will reduce a large portion of her damage, reducing the chances that Legion Commander will win the duel.
* Spear of Mars and God's Rebuke pushes Legion Commander away during Duels against allies.

* Spirit Breaker won’t do much harm because of Untouchable and Nature's Attendants. Unless Enchantress is low on HP, Spirit Breaker won’t catch her with mere spells.

* Heroes with abilities that blind or cause Legion Commander to miss will prevent her from winning Duels: Arc Warden, Keeper of the Light, Riki

* Heroes that punish mobile heroes: Bloodseeker, Keeper of the Light