* Chain Frost can eliminate Chaos Knight's Phantasm army, especially after he clumped up using Reality Rift.
* Frost Shield will heavily reduce his army's effectiveness.
Additional:
* Lich's Chain Frost, especially after obtaining its respective talent that provides unlimited bounces, can take out all of Chaos Knight's illusions quickly.

* Chain Frost will bounce between Lone Druid and his bear, forcing them to separate or suffer high amounts of damage.
Additional:
* Chain Frost can deliver high amounts of damage to Lone itself and his bear if they do not separate fast from each other.

* Maledict cannot be dispelled by Phantasm, and can be used to tag the real Chaos Knight hiding within his illusions.
* If Witch Doctor has an Aghanim's Scepter, Death Ward will bounce between Chaos Knight's illusions, destroying them quickly.
* However, Death Ward is easily interrupted by Chaos Bolt until Witch Doctor buys Glimmer Cape or Black King Bar.

* Paralyzing Cask is likely to bounce between him and his bear every single time.
* Lone Druid's lack of mobility makes him vulnerable to Death Ward and Maledict.

* Cold Embrace protects targets of Reality Rift.
* Winter's Curse turns Phantasm illusions against Chaos Knight or a teammate.
* Splinter Blast deals decent area damage to Phantasm illusions.
* Arctic Burn's percentage-based damage quickly wears down Chaos Knight's health.
Additional:
* Winter Wyvern can make Chaos Knight's illusions attack the real one, provided the player knows who it is.
* Alternatively, Winter's Curse can make Chaos Knight and all his illusions attack one of his allies.
* Cold Embrace protects ally who is focused by Chaos Knight.
* Splinter Blast deals decent area damage to Chaos Knight's illusions.

* Cold Embrace can protect allies from Lone Druid and the Spirit bear, who mainly deal physical damage
* Winter's Curse can turn Lone Druid and the Spirit Bear against his teammates.

* Storm's Dispel Magic combined with Thunder Clap deals high damage against Chaos Knight's illusions even in the late game.
* Chaos Knight's reliance on physical damage is easily hindered by Drunken Brawler.
* Chaos Knight's lack of area effect and mobility makes him easily overwhelmed by Primal Split.
Additional:
* Dispel Magic from {U:Storm} can instantly kill the Phantasm army early game and can still deal a lot of damage to them late game, revealing the real Chaos Knight.

* Brewmaster can make the Spirit Bear a much smaller threat with Cinder Brew.
* Cyclone removes the bear from a fight so that his team can easily focus on the hero.
* While most heroes would be worn down by a Spirit Bear Radiance in the time it takes to kill Lone Druid, Brewmaster is protected in Primal Split.

* Chaos Knight's single target abilities are difficult to target against Phantom Lancer's illusions.
* Chaos Knight's lack of mobility makes him an easy target for Phantom Lancer to rush and drain of mana.
Additional:
* Juxtapose allows Phantom Lancer to overwhelm Chaos Knight due to his single-target abilities.
* Doppelganger can be used to dodge Chaos Bolt.
* Spirit Lance can be used to harass Chaos Knight during the early game.
* Since Phantom Lancer build Diffusal Blade often, it can quickly drain Chaos Knight of all his mana, leaving him unable to cast spells.

* Lone Druid and his Spirit Bear lack mobility, and are easy overwhelmed after being slowed by Diffusal Blade.

* Quill Spray quickly destroys Chaos Knight's Phantasms.

* Lone Druid and The Spirit Bear cannot burst down Bristleback due to Bristleback
* Bristleback can easily run to Lone Druid without any hesitation, with Viscous Nasal Goo to reduce armor and slow the Spirit Bear or Lone Druid and Quill Spray can deal damage to both Lone Druid and the Spirit Bear at the same time

* Pugna: Decrepify prevent the Spirit bear from attacking or protect allies from it.

* Decrepify turns the target ethereal, protecting them from Chaos Knight's and his illusions' attacks.
* Life Drain instantly destroys illusions. It can effectively negate Phantasm when upgraded with Aghanim's Scepter.
* Nether Blast quickly clears out illusions and can harass Chaos Knight in lane.

* Lone druid's bear attacks on Phoenix's Supernova Egg don't increase the hit count. Given that Lone Druid's main hero often doesn't have much farm, the Supernova Egg is less likely to get killed.

* Illusion-based heroes such as Naga Siren or Chaos Knight are vulnerable to Phoenix's DPS and attack speed slow, as their illusions, no matter how many, will be unable to deal enough damage to actually be a threat, and they will all be completely useless against the Supernova.

* Ensnare is good vs bear.
* In teamfights, song of the siren may be used to properly set up and coordinate an attack on Lone Druid in the backline, bursting him down, allowing to completely ignore the bear.
* Druid lack innate AoE capabilities giving him no good way of dealing with illusions.

* Illusion-based and multi-unit heroes can take advantage of Chaos Knight's lack of area damage: Naga Siren, Phantom Lancer, Meepo, Broodmother

* Timbersaw: Lone Druid will have a hard time dealing with Timbersaw due to his tankiness and high Armor from Reactive Armor

* Reactive Armor helps Timbersaw to endure the damage from Chaos Bolt and Reality Rift combo.
* Timbersaw's large amount of pure damage AoE nukes clears Chaos Knight's illusions quickly, drastically reducing his damage.
Additional:
* Strong area damage, particularly from Whirling Death and Chakram, lets Timbersaw clear out illusions quickly.
* Whirling Death directly reduces Strength from both Chaos Knight and his Phantasm illusions, reducing both the damage output and raw health that the hero relies on.
* Reactive Armor quickly builds stacks against Phantasm illusions, making Timbersaw hard to kill.
* Timber Chain allows Timbersaw to escape while surrounded.

* Arcane Orb deals heavy damage to both Lone Druid and the Spirit Bear.
* Astral Imprisonment can prevent the Spirit Bear from attacking, which is Lone Druid's main damage output.
* Sanity's Eclipse deals heavy damage to Lone Druid.

* Illusion based heroes (like Chaos Knight and Terrorblade) can't use their illusion beneficially against Sanity's Eclipse's high AoE burst damage.

* Heroes who are reliant on illusions or summons: Chaos Knight, Broodmother, Naga Siren.

* Grimstroke's Soulbind will always reliably connect onto both of them if they are close together.

* With Aghanim's Scepter, Tinker's Laser completely stops Chaos Knight's damage, forcing him to buy either a Black King Bar for his own survivability while leaving his illusions still vulnerable, or a Monkey King Bar leaving him still vulnerable to Tinker's nukes, though improving his damage.
* Tinker rarely finds himself in the middle of a fight, which is where Chaos Knight typically thrives, and even in the rare cases of being so, at level 3 Tinker's constant rearm and blink away can kite and dodge Chaos Knight's spells reliably, so Chaos Knight has very little catch against Tinker's mobility. This gives Tinker impunity to create more chaos in a teamfight than Chaos Knight can control, laying down the field with March of the Machines and constantly being hit by rockets and lasers.
Additional:
* Tinker's Aghanim's Scepter upgraded Laser can blind him and all of his Phantasm illusions.

* Laser blinds Lone Druid, making his attacks miss. Furthermore, a Tinker with Aghanim's Scepter is sure to blind both Lone Druid and his bear, negating his ability to root or deal physical damage.

* Phantasms can be easily killed with Purification.
* Heavenly Grace dispels the stun from Chaos Bolt and the armor reduction from Reality Rift.
* Guardian Angel works well against Chaos Knight's overwhelming reliance on physical burst damage.
Additional:
* Purification heals a teammate targeted by Reality Rift and heavily damages Chaos Knight and his illusions in the process.
* Guardian Angel blocks all of Chaos Knight's damage for a duration.

* Ghost Shroud can be use both offensively to slow Lone Druid or Defensively to prevent Lone Druid and The Spirit Bear from attacking him.
* Heartstopper aura burns the Spirit bear High HP over time. Additionally, it can deal decent damage to Lone Druid during his True Form.

* Heroes that have high health but little to no magic resistance are easy prey for Necrophos, as no matter how high they build their health up, Reaper's Scythe will kill them outright as long as they fall under a certain threshold, and Heartstopper Aura will deal the same amount of damage regardless, decaying their health the longer they stay within range. As such, Strength heroes like Chaos Knight, Centaur Warrunner or Magnus are good targets for his ultimate.

* Ravage damages and disables Chaos Knight's army.
* Anchor Smash deals respectable area damage at early levels and lowers Chaos Knight's damage.
* Kraken Shell dispels Chaos Bolt and Reality Rift while providing protection from damage.

* Great Cleave is very effective against Chaos Knight's illusions.
* Storm Hammer's radius can catch all of Chaos Knight's illusions at once, especially after Reality Rift.
* Warcry shields Sven and his teammates against Chaos Knight's burst physical damage.
Additional:
* Sven's shorter cast time allows him to use Storm Hammer on Chaos Knight and his illusions before he can cast Chaos Bolt.
* Warcry's armor bonus counteracts Reality Rift's slow and reduces Chaos Knight's damage output.
* Great Cleave and God's Strength devastates Phantasm illusions.

* The area of effect damage from Midnight Pulse and Black Hole help deal with Chaos Knight's illusions.
Additional:
* Black Hole usually catches Chaos Knight with all his illusions.
* Midnight Pulse deals damage based on max health, quickly killing Phantasm illusions.

* With his AoE damage, Jakiro can easily kill Chaos Knight's Phantasm illusions.
* Chaos Knight usually doesn't buy a Black King Bar, making him vulnerable to an Ice Path into Macropyre combination.
Additional:
* Ice Path and Macropyre punish Reality Rift with a long stun and heavy damage across all illusions.

* Abaddon could punish Chaos Knight for using Phantasm and Reality Rift combo on him with his Aphotic Shield. Additionally, it provides extra protection against Chaos Knight's potential to take Abaddon down quickly.
* Furthermore, Abaddon's Borrowed Time makes it utterly impossible to burst Abaddon down.

* Berserker's Call and Counter Helix makes short work of Chaos Knight's Phantasms.
Additional:
* Berserker's Call allows Axe to lock down Chaos Knight and his illusions.
* Counter Helix combined with Blade Mail clears illusions out in no time.

* Using Reality Rift sets up a Reverse Polarity on Chaos Knight and his illusions.
* Shockwave and Skewer kill Phantasm's illusions quickly, as can Empower cast on a melee carry.
Additional:
* All Magnus abilities are very good against Chaos Knight's Phantasm illusions.

* Echo Slam's damage potential increases due to Chaos Knight's Phantasm illusions.
Additional:
* Echo Slam will deal a colossal amount of damage to your army, as will Fissure at lower levels.
* The area stuns from Aftershock will always slow down your illusions, since they can't have spell immunity.

* Lone Druid during True Form and the Spirit bear has high HP, meaning Spirit Siphon can be very effective against them since they deal percentage damage

* Puck's area of effect nukes in the form of Illusory Orb and Waning Rift clears Phantasm illusions from the early game to mid game.
* Phase Shift can be used to disjoint Chaos Bolt.

* Wukong's Command and Boundless Strike combo can easily cause havoc on Chaos Knight by destroying all of his powerful illusions.
* Chaos Knight without Phantasm cannot deal with Jingu Mastery at all.

* Morphling can ignore Spirit Bear and shorten the distance to Lone Druid with Waveform.
* Morphling can use his nukes to burst Lone Druid down, provided he is not rooted/disabled by Spirit Bear beforehand.

* Dragon Blood's armor bonus greatly reduces the damage dealt by Phantasm.
* Breathe Fire and Elder Dragon Form's splash damage quickly destroy illusions and reduces their damage output.

* Ember Spirit is evasive and can dodge close encounters with melee heroes like Chaos Knight. Ember Spirit can't be caught with the slow from Reality Rift, and Flame Guard and Sleight of Fist can bring Phantasm's illusions down quickly.

* Tidebringer, Torrent and Ghostship destroys Chaos Knight's Phantasm army all through the game.

* Flak Cannon destroys Chaos Knight's illusions very quickly.

* Illusion-based and multi-unit heroes can take advantage of Chaos Knight's lack of area damage: Naga Siren, Phantom Lancer, Meepo, Broodmother

* Heroes that rely on illusions will suffer against Ion Shell, which kills them very quickly: Phantom Lancer, Chaos Knight, Naga Siren, Meepo.
* Heroes that rely on illusions typically spawn very strong illusions inside your Wall of Replica that you should use against them or their team.

* 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.

* Riki: Smoke Screen can prevent Lone Druid from using True Form and Savage Roar, additionally it cause the spirit bear to miss on attacks which reduce the chances of getting rooted from it, with diffusal Blade, he can keep Lone Druid or the Spirit Bear inside the Smoke.

* Heroes who rely on illusions can be tagged by Focus Fire: Chaos Knight, Terrorblade.

* Because of his massive AoE damage, Sand King is very effective against illusion heroes: Chaos Knight, Phantom Lancer, Terrorblade,...

Additional:
* Sand King's massive area damage output, particularly Epicenter, allows him to quickly take down Chaos Knight and his illusions.
* He can apply Caustic Finale to illusions with attacks for extra damage.

* Heroes reliant on illusions or summons: Broodmother, Chaos Knight, Naga Siren.

* Heroes who are illusion based, or even heroes who frequently build Manta Style can be cleared quickly by Pangolier's high damage, or lose their damage ouput because of Lucky Shot: Chaos Knight, Naga Siren

* Heroes who are reliant on illusions: Chaos Knight, Phantom Lancer, Naga Siren.

* Heroes who rely on illusions will see them destroyed easily by Overwhelming Odds: Phantom Lancer, Chaos Knight, Terrorblade, Naga Siren

* One of Lion's level 20 talents lets Mana Drain affect 2 secondary targets. This can make things difficult for heroes like Phantom Lancer, Chaos Knight, and Terrorblade who rely on illusion armies.
* Mana Drain and Hex instantly kill any illusions. Finger of Death upgraded with Aghanim's Scepter also shreds most illusions.
* One of Lion's level 20 talents lets Mana Drain affect 2 secondary targets. This can make things difficult for heroes like Phantom Lancer, Chaos Knight, and Terrorblade who rely on illusion armies.

Additional:
* Mana Drain is a real problem to Chaos Knight early game, considering his already low mana pool.
* Aghanim's Scepter upgraded Finger of Death is an AoE ability, which can deal a tremendous amount of damage to his illusions.
* Hex with a level 25 talent instantly disposes Chaos Knight's illusions.

* Illusion-based and multi-unit heroes can take advantage of Chaos Knight's lack of area damage: Naga Siren, Phantom Lancer, Meepo, Broodmother

* Blur allows Phantom Assassin to escape from Lone Druid and the spirit bear. Additionally, it provides evasion which effectively reduce the damage output from the Spirit Bear and reduce the chances to root her, forcing him to invest in Monkey King Bar
* At late game, Phantom Assassin out carry Lone Druid.