* Heroes with AoE abilities will hit Slark in Shadow Dance: Lina, Jakiro, Underlord, Leshrac, Dark Seer, Earthshaker, Timbersaw, Crystal Maiden

* Dark Pact is minimally effective against Phantasm illusions, and Slark lacks area damage otherwise.
* Pounce can be counteracted by Reality Rift.
* Slark is naturally frail and dies quickly to Chaos Knight's burst damage before he can build Essence Shift stacks.
* Be aware, however, that Shadow Dance can make Slark hard to kill as he can't be targeted during its duration.
Additional:
* Phantasms have enough health to survive Dark Pact, and Slark has no other source of AoE damage to deal with them.

* Diabolic Edict and Pulse Nova will tear apart any illusions spawned from Disruption
* Split Earth can punish improper usage of Disruption.
* Leshrac does not have any buffs that can be removed by Demonic Purge.
Additional:
* Pulse Nova makes quick work of any illusions with amplified damage, and deals damage even if Leshrac is in Disruption.
* An attempt to save an ally using Disruption can easily become a perfect setup for a Split Earth for the enemy.
* Disruption does not stop Diabolic Edict and Pulse Nova once they start pulsing, and even worse it provides a safe shelter for Leshrac to keep pumping up his powerful AoE damage onto the battlefield.
* Leshrac usually builds Eul's Scepter of Divinity to dispel Shadow Poison and Soul Catcher and Linken's Sphere to block Disruption and Demonic Purge.
* Shadow Demon doesn't have the burst damage to take Leshrac out of the fight quickly, although Demonic Purge can help his allies kill a squishy Leshrac.

* Chaos Knight, Lone Druid, Meepo and Arc Warden can be hard targets since Shadow Demon's spells are ill-suited to fight many enemies at once.

* Illusion and heroes with summons are difficult to kill with Chen's single-target offensive spells: Terrorblade, Phantom Lancer, Chaos Knight, Broodmother, Naga Siren, Lycan, Visage. However, Chen can convert enemy summons with Holy Persuasion, as long as they don't bunch up.

* Leshrac's AoE abilities make quick work of Chen's creep army.

* Diabolic Edict and Pulse Nova hit all units around Leshrac, making it very easy for him to kill the Summon Familiars.
* Diabolic Edict and Pulse Nova also deal many instances of damage, nullifying Gravekeeper's Cloak.
* Split Earth and Lightning Storm makes it difficult for Visage to kite Leshrac, even while under the effects of Grave Chill.

* Heroes that can overwhelm Visage by sheer number like Chaos Knight, Meepo, Terrorblade and Phantom Lancer.

* Reality Rift pulls out Night Stalker while he tries to escape or chase.
* Night Stalker doesn't have a lot of ways to deal with multiple targets, which makes him vulnerable to Phantasm illusions from early to mid game, until Night Stalker buys Aghanim's Scepter.

* Heroes that can punish aggressive heroes, such as: Leshrac, Shadow Demon, Pugna, Death Prophet.

* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Pugna

* Heroes that have disposable area-targeted spells can force her to undo her Meld: Leshrac, Puck, Tiny. An experienced Templar Assassin could try to Refraction before Meld so she can tank through those damage without getting her Blink disabled.

* Heroes who summon multiple units that are not spell immune. Nature's Prophet,Lycan,Beastmaster

* Single-target disablers will have difficulty locking down a Chaos Knight with Phantasm active: Bane, Beastmaster, Bloodseeker, Clockwerk, Doom, Shadow Shaman.

* Wraith King has no form of AoE to clear Chaos Knight's illusions from Phantasm.
* Wraith King is very vulnerable if he reincarnates in the middle of his illusions.

* Phantasm's illusions make it difficult to land Meat Hook and Dismember.
* Chaos Bolt is a comparatively low cooldown tool to interrupt Dismember.
* Chaos Strike's lifesteal offsets Rot's damage.

* While Chaos Knight can land far away from Rubick due to Telekinesis, it can be counteracted by Reality Rift.
* Phantasm dispels Fade Bolt's damage reduction debuff.
* Rubick is fragile and can easily be killed by Chaos Knight and Phantasm's illusions, before he retaliates.

* Chaos Knight's tanky illusions easily take advantage of Troll Warlord's lack of AoE damage.
* Chaos Bolt can stun Troll for up to 4 seconds and Reality Rift prevents Troll Warlord from chasing down foes.
* Phantasm increases Chaos Knight's physical damage output up to 4 times and can easily kill Troll Warlord before he has a chance to use Battle Trance or a Black King Bar.

* Phantasm's illusions can be used to push towers and force Techies to detonate Remote Mines.
* Phantasm's illusions can be used to sweep Proximity Mines and Stasis Traps.
* Chaos Knight can easily kill a lone Techies before they Blast Off!.

* Casting Phantasm before a fight minimizes the disruption from Global Silence.
* Because Chaos Knight generally relies on attack damage, Silencer's spells won't be as effective against him.

* Lightning Storm will usually hit both Io and its tethered target since both will be close enough for the lightning to jump.
* Diabolic Edict and Pulse Nova hit all units near Leshrac, meaning he can do colossal damage to Io and its tethered target.
Additional:
* Lightning Storm will usually hit both Io and his Tethered target since both will be close enough for the lightning to jump. It can then be followed up by Split Earth.
* Diabolic Edict and Pulse Nova hit all units near Leshrac, meaning he can do colossal damage to Io and his Tethered target.

* Phantasm dispels Track, and the illusions make it difficult to Track the real Chaos Knight.
* Bounty Hunter is fragile and can easily be killed by Chaos Knight and Phantasm's illusions.

* Viper has no response to the standard initiation combo of Reality Rift into Chaos Bolt.
* Phantasm can eliminate Viper almost instantly with its damage output.
Additional:
* As Viper focuses on single-target damage, he has trouble fighting off Phantasm illusions.
* Reality Rift counteracts Viper's slows and reduces his durability.

* Reality Rift lets Chaos Knight bypass the Spirit Bear and jump onto Lone Druid.
* The Spirit Bear's lack of scaling means it dies quickly to Chaos Knight during the late-game.

* Chaos Knight can dispel Flux with Phantasm.
* Chaos Knight can use Reality Rift to pull Arc Warden out of Magnetic Field.
* Once Chaos Knight jumps on Arc Warden with Reality Rift, Arc Warden struggles to escape due to low mobility.

* Phantasm dispels Ignite and makes targeting the real Chaos Knight much harder.

* Reality Rift will disable Drow Ranger's Marksmanship, along with Chaos Bolt he can keep her locked for enough time to be killed.
* Phantasm's illusions are hard for Drow Ranger to deal with as she lacks of AoE damage.

* Razor has no way to deal with Chaos Knight's multiple illusions from Phantasm.

* Chaos Knight's high health pool makes him resistant to Zeus' burst damage. Phantasm can dispel Veil of Discord, a typical item purchased by Zeus.
* Zeus is easily overwhelmed by Chaos Knight's strong illusions, as Arc Lightning is not enough to kill them fast enough to have any impact.
* Zeus' low base armor makes him extremely vulnerable to Chaos Knight's high damage output and armor reduction.

* Heroes that have AoE damage: Lina, Keeper of the Light, Timbersaw, Leshrac, Bristleback, Axe

* Ursa struggles against illusion heroes like Chaos Knight and Phantom Lancer.

Additional:
* Ursa cannot effectively fight against Phantasm's illusions with his single-target damage.
* Chaos Bolt's potentially long stun with Chaos Bolt gives Ursa little opportunity to Enrage.

* Heroes who summon multiple units that are not spell immune. Nature's Prophet,Lycan,Beastmaster

* Chaos Knight with Phantasm
* Heroes that can dodge Glimpse:
* Puck with Phase Shift
* Riki with Tricks of the Trade
* Phantom Lancer with Doppelganger
* Ember Spirit with Sleight of Fist and Activate Fire Remnant
* Chaos Knight with Phantasm
* Naga Siren with Mirror Image
* Tusk with Snowball
* Juggernaut with Omnislash
* Brewmaster with Primal Split
* Lifestealer with Infest
* Phoenix with Supernova

Additional:
* Phantasm removes Glimpse and dispels Thunder Strike. Additionally, the Phantasm illusions make it difficult to use Glimpse and Thunder Strike on the real Chaos Knight.
* Disruptor's lack of mobility, combined with his lack of innate defense, sets him up for a Reality Rift and a beatdown by Chaos Knight and his illusions.

* Single-target disablers will have difficulty locking down a Chaos Knight with Phantasm active: Bane, Beastmaster, Bloodseeker, Clockwerk, Doom, Shadow Shaman.

* Heroes with illusions and summons can be hard for Phantom Assassin to deal with, as she lacks any AoE abilities to deal with them: Broodmother, Phantom Lancer, Chaos Knight.

* Skywrath mage also has a terrible time fighting against anything that isn't a hero. As Mystic Flare only affects heroes, his skills are mostly target-based and he has terrible strength and agility, he can easily be kited or harassed by illusion-based heroes like Chaos Knight and Phantom Lancer, or by Heroes that summon other units like Lone Druid, Lycan and Beastmaster.

* Single-target disablers will have difficulty locking down a Chaos Knight with Phantasm active: Bane, Beastmaster, Bloodseeker, Clockwerk, Doom, Shadow Shaman.

* Heroes that create illusions (such as Spectre, Shadow Demon, Phantom Lancer, Naga Siren, Chaos Knight, Terrorblade) or bring other units into the fight (such as Nature's Prophet, Lone Druid, Chen, Enchantress and the aforementioned Meepo and Arc Warden) can cause Eclipse to strike the illusions/summons unintentionally. (However, in many cases Moon Glaives can resolve this issue and eliminate them before activating Eclipse).

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

* Warlock is a very strong hero when positioned correctly, and his long cast range helps him with this. However, some Heroes might disrupt or sneakily pass through your allies and deal with you, preventing you from doing your job. Such heroes include Chaos Knight, Spirit Breaker, Riki, and some others.

* Heroes with illusions and summons can swarm Bane, who has no area abilities: Broodmother, Chaos Knight, Nature's Prophet, Phantom Lancer, Terrorblade

Additional:
* Phantasm's illusions make it difficult for Bane to target Chaos Knight with Nightmare, Brain Sap and Fiend's Grip.
* Chaos Bolt is a comparatively low cooldown tool to interrupt Fiend's Grip.
* Nightmare can be transferred by Phantasm illusions.

* Heroes who relies on illusions and summons (Beastmaster, Chaos Knight, etc.).

* Chaos Knight's multiple illusions from Phantasm can destroy Undying, as Soul Rip can't offset the damage from the high amount of damage from his illusions.

* Heroes with illusion and clone abilities may confuse Bloodseeker, causing him to waste time in fights: Phantom Lancer, Chaos Knight, Arc Warden

* All of Leshrac's abilities, especially Pulse Nova can easily deal with Naga Siren's illusions.

* Pulse Nova deals an insane amount of damage in an area around him, which can quickly wear down Meepo clones.
* Leshrac can catch multiple Meepos in Split Earth and follow up with the rest of his area damage spells making meepo unable to get close to leshrac.
* Diabolic Edict is a strong ability that can wear down a lone Meepo clone quickly.

* While Blade Fury is on cooldown, Juggernaut can easily killed by a standard Chaos Bolt & Reality Rift combo.
* Phantasm illusions can tank Omnislash.

* Your AoE abilities should make quick work of her spiderlings.

* Leshrac's AoE abilities destroy Phantom Lancer's illusions.
* Diabolic Edict and Pulse Nova require no targeting, thus hitting Phantom Lancer whenever he's nearby.
Additional:
* Leshrac can easily clear Phantom Lancer's illusions with his huge area of effect damage.

* 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.

* Chaos Knight's Level 20 Talent: Reality Rift Pierces Spell Immunity allows for quick bursting down of Lifestealer during his Rage.
* Phantasm dispels Open Wounds.
* Lifestealer has no way of dealing with Chaos Knight's illusions.

* Since Windranger is bad against magical damage, heroes with continuous magical damage or magical nukes can blast her: Zeus, Tinker, Leshrac, Viper, Skywrath Mage, Lion, Lina, Venomancer.

* Heroes with illusions can overwhelm Huskar, as he has no AoE abilities: Phantom Lancer, Anti-Mage, Arc Warden, Chaos Knight.

* Illusions make it difficult for Necrophos to target his Reaper's Scythe correctly, thus giving illusion heroes like Chaos Knight or Naga Siren an edge against Necrophos.

* Innately fragile heroes will die almost instantly to Reality Rift while Chaos Knight has illusions active: Drow Ranger, Bane, Necrophos, Crystal Maiden.

* Single-target disablers will have difficulty locking down a Chaos Knight with Phantasm active: Bane, Beastmaster, Bloodseeker, Clockwerk, Doom, Shadow Shaman.