* Familiars will be able to chase Spectre through the trees when she uses Spectral Dagger, while Visage can keep blasting her with Soul Assumption.
* Desolate will almost never proc because Visage will always have nearby Familiars.

* 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.

* 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

* Nether Blast is one of the best tower pushing abilities in the game, with a low cooldown. A competent Pugna will (at the very least) destroy tier 2 towers and make space for his team before Spectre can finally come online.
* Spectre's spells, while not spammable, have a fairly high mana cost, so Nether Ward can be fairly damaging to Spectre early game. The mana degen will also dampen Spectre's early game power significantly.
* Once Pugna gets Aghanim's Scepter, he can spam Life Drain on any illusion Spectre summons, whether it'd be from Haunt, Manta Style, or some other means.
* In addition, Pugna can disable Spectre's Desolate ability (although its damage is pure, it requires physical attacks) with his Decrepify ability, leaving Spectre only with Spectral Dagger.

* Global Guardian Angel will protect his allies from Spectre's Haunt, both when they are alone and in teamfights.
* Purification is a major problem for melee enemies, Spectre included, since they must be next to an enemy in order to attack. The AoE damage also allows Spectre to be singled out from her illusions.
* Degen Aura will prevent Spectre from chasing Omniknight, further exacerbated by her terrible mobility outside Haunt.

* 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.

* 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.

* Arctic Burn makes it nearly impossible for Spectre to juke into the trees.
* Cold Embrace negates all of Spectre's physical damage. Furthermore, Cold Embrace will generally outheal Desolate.
* Winter's Curse can taunt illusions, not only wasting the entire duration of Haunt but also turning its illusions against Spectre's own team.

* 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.

* Poof combined with Earthbind can be used to easily lockdown and burst Spectre down.
* As Meepo's playstyle is often to come online early to mid game and take over the whole game, Meepo will often be much further ahead of Spectre in farming.
* Meepo's global map presence allows him to effectively hunt for Spectre and disrupt her farm.
* Spectre has no strong AOE abilities or way to control or lock down Meepo.

* 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.

* Slardar's Slithereen Crush allows him to stun Spectre and illusions, and Corrosive Haze prevents her from juking with Spectral Dagger.

* Spectre cannot have a good game if she is pressured heavily in lane, which is something Mars can do.
* Spectre can use Haunt and Spectral Dagger inside and outside from Arena of Blood, but it doesn't really matter since Mars does best during the early and mid game.
* Should Spectre get to the late game, Mars can block a large amount of her damage and split the teamfights in his advantage.

* 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.

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

* Stone Gaze negates Dispersion's damage reduction and allows Medusa to kite Spectre.
* Spectre's small mana pool is depleted quickly by Mystic Snake.
* Split Shot can clear Haunt illusions quickly.

* 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.

* Wave of Terror can reduce Legion Commander's survivability during a Duel.
* Magic Missile and Nether Swap disrupts Duels and saves allies.

* 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.

* Spectre must chase for kills and relies on movement speed for mobility in fights, and has no way to counter the Tombstone zombies.
* The potency of Soul Rip can be increased from nearby illusions from Haunt.
* Decay will shut down Spectre during the laning phase by effectively cutting down her initial health pool.
Additional:
* Spectre must chase for kills and relies on movement speed for mobility in fights, and has no way to counter the Tombstone zombies.
* The potency of Soul Rip can be increased from nearby illusions, so Undying can use Haunt against Spectre.
* Early game Decay will make Spectre easy to shut down in lane.

* Ball Lightning is the ultimate counter to Spectre's entire toolkit. With this ability, he can score easy kills on Spectre without her having any means of escape early game, kite her and her Haunt illusions when it's later in the game due to her having no form of pseudo-blinks. Furthermore, it is very difficult for Spectre to deal any substantial damage against Storm Spirit with Desolate, and without both a Manta Style and a Diffusal Blade he will always remain on the move. Also, Ball Lightning grants invulnerability, and as Storm Spirit likes to spam that ability, he can mitigate the damage done from Dispersion and Radiance.
Additional:
* Storm Spirit can exploit every one of Spectre's weaknesses, and thus is one of the best counters against her.
* Spectre has to be in melee range to deal damage, making her likely to trigger Static Remnants and susceptible to being kited by Overload procs.
* Electric Vortex can lock Spectre down as she doesn't like to build Black King Bar.
* Ball Lightning gives Storm Spirit multiple advantages:
* Spectre cannot evade Storm Spirit, as Ball Lightning is superior to Spectral Dagger in terms of mobility.
* Storm Spirit can kite her and her Haunt illusions when it's later in the game due to her having no form of pseudo-blinks (Reality is far inferior to Ball Lightning).
* It is very difficult for Spectre to deal any substantial damage against Storm Spirit with Desolate. Ball Lightning grants invulnerability and can mitigate damage done from Dispersion and Radiance.

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

* Nethertoxin disables Desolate and Dispersion, leaving Spectre with far less damage output and damage mitigation in engagements.
* Spectre is one of the weakest heroes at early levels. Viper can stifle her farm with early fights before Spectre purchases any major items.
Additional:
* Nethertoxin removes passives, negating Spectre's damage and survivability by removing both Dispersion and Desolate.
* Due to Haunt and Radiance's burn, Spectre is heavily susceptible to being persistently slowed and damaged by Corrosive Skin without even directly attacking Viper.
* Poison Attack and Viper Strike further slow Spectre's movement speed to a crawl, while his improved magic resistance means he can easily shrug off Radiance's burn.

* 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.

* 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.

* Infernal Blade's damage is calculated by percentage of maximum health, meaning that it will hurt Spectre more than most normal attacks, negating some of her tankiness.
* With Aghanim's Scepter Dispersion and Desloate are disabled.
* Doom can pick up several different abilities from neutral creeps using Devour, some of which can be annoying to Spectre.
* Mud Golem, Dark Troll Summoner, Harpy Stormcrafter, Satyr Mindstealer or Satyr Tormenter are good examples.
* Doom makes Spectre less disruptive.

* 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.

* Hex and Mana Drain can be used to immediately destroy Spectre's illusion when she Haunts. A fast fingered Lion can protect himself and a teammate.
* Hex and Earth Spike are good lockdown spells to control and kill Spectre, especially if she doesn't buy defensive items like Linken's Sphere and Black King Bar.
* Finger of Death can be used to burst down Spectre when she is low on life as she has very poor magic resistance.

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

* 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.

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

* 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.

* 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.

* Her illusions with Desolate is very valuable, especially when they are usually paired with Radiance. Unlike blink or force movement, Spectral Dagger's escaping mechanic requires manual movement, and therefore Demonic Purge can hold her back really hard allow your allies to finish her off.
* If she would try to kill you or any key ally with Haunt at any point of the game, remember to not panic and always use Disrupt on the illusion, whether it is fake or the real Spectre herself. When the situation calls, Demonic Purge can save a second victim from a haunting Spectre.
* When upgraded by Aghanim's Scepter, Demonic Purge can remove Spectre from a fight by disabling Desolate and Dispersion, negating her damage and tankiness respectively.

* Dark Seer can pull together Spectre's illusions with Vacuum, and Wall of Replica creates an illusion of Spectre that deals massive damage.

* Zeus is good against heroes that juke in trees or up cliffs, like Batrider, Monkey King, Spectre, and Tinker, by providing vision in any area with Lightning Bolt, or guaranteeing vision on enemies with Thundergod's Wrath.

* 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

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

* 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.

* 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.

* Jakiro's early pushing ability from Liquid Fire makes Jakiro very strong against heroes, that take a long time to get online: Morphling, Naga Siren, Spectre.

* 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.

* Disruptor can control where she goes with Kinetic Field and Glimpse. Static Storm shuts her down in teamfights.

* 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 good escapes can usually outmaneuver and escape from Spectre: Slark, Clinkz, Weaver

Additional:
* Essence Shift deals 20 extra damage by draining one strength per hit, which cannot be reduced or spread by Dispersion.
* Pounce prevents Spectre from escaping from or chasing with Spectral Dagger.
* Haunt illusions usually don't deal a lot of damage to Slark as he tends to buy a Shadow Blade, preventing Desolate's and Diffusal Blade's damage and activating Shadow Dance's regeneration to make up for any damage caused by Radiance.

* 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.

* 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

* Dispersion will not do anything against throughout the game due to his high lifesteal with Jingu Mastery.
* Monkey King often buys Manta Style, which will deny Desolate benefits in 1v1 situations.
* Haunt will do nothing to stop people trapped within Monkey Kings ultimate.
* In all, Spectre is very easily pressured by Monkey King early into the game and is a very easy gank target to coordinate with your team.

* Death Pulse can single out Spectre from her illusions, as well as heal his team against her. He also usually stands close to his allies for Death Pulse, effectively disabling Desolate.

* 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.

* Venomancer's poison damage-over-time are very effective against Spectre, which is lack of magic resistance from early to mid game.
* Venomancer's multiple slows greatly reduces Spectre's low mobility, even through Spectral Dagger.
* Plague Wards reveals Spectre while she is hiding on trees.
Additional:
* Venomancer's poison damage over time is very effective against Spectre, who tends to lack magic resistance during the early to mid game.
* Venomancer's multiple slows greatly reduces Spectre's movement speed and mobility.
* Plague Wards can scout out Spectre while she is hiding in trees.

* The movement speed granted from Shapeshift means that Spectre has no way to punish Lycan if he wants to splitpush or pick off supports. Furthermore, he will kite Haunt and cannot be slowed by Spectral Dagger.
* As Lycan typically has Summon Wolves out and builds Necronomicon, very rarely will he be damaged by Desolate if he does manage to get into a fight against her.
* Lycan is often part of an early game push strategy which is often the best counter to Spectre because she needs a lot of time and space to come online as a late game carry.

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

* Hex can be used immediately to destroy Spectre's illusion when she Haunts.
* Shadow Shaman can use Shackles to lock down Spectre for his team.
* Shadow Shaman's Mass Serpent Ward and Ether Shock help him push lanes and end the game early before Spectre can come online and take over the late game.

* Song of the Siren lasts long enough to prevent a successful Duel (but only if Naga wasn't the target).

* 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.