Lion
[wiki] rating: 1.6 (winrate: 50% pickrate: 17%)Queen of Pain
[wiki] rating: 1.2 (winrate: 47% pickrate: 9%)Keeper of the Light
* Heroes with teleports to escape Will-O-Wisp: 
Phantom Assassin, 
Puck, 
Queen of Pain, 
Storm Spirit
Brewmaster
* Blinking heroes like 
Anti-Mage or Queen of Pain can often chase down an injured Brewmaster after his ultimate expires.
Bane
[wiki] rating: 1.0 (winrate: 54% pickrate: 3%)Brewmaster
* After Brewmaster has committed Thunder Clap and Cinder Brew to gank, Bane can use 
Nightmare on Brewmaster to wait out the debuffs, and might even turn the tables by buying time for allied reinforcements.
* Bane can also prevent Brewmaster from using Primal Split with his long disables.
Night Stalker
[wiki] rating: 1.0 (winrate: 52% pickrate: 5%)Keeper of the Light
* 
Crippling Fear prevents Keeper of the Light from using his spells to keep his team alive during team-fights.
* 
Dark Ascension is very strong against Keeper of the Light, who relies on daytime to be effective.
Additional:
* Keeper of the Light's 
Aghanim's Scepter upgrade loses much of its power, due to Night Stalker being able to reduce the duration of daytime by a lot.
Shadow Shaman
[wiki] rating: 1.0 (winrate: 52% pickrate: 16%)Brewmaster
* 
Hex's instant cast time will force Brewmaster into the awkward situation of needing some form of spell immunity or block to prevent being immediately hex upon blinking in, or wait until Shaman has used all his crowd control before entering a fight.
* Brewmaster also has no defense against Shadow Shaman lockdowns.
Death Prophet
[wiki] rating: 1.0 (winrate: 51% pickrate: 10%)Brewmaster
* 
Exorcism kills Primal Split's units very quickly.
Outworld Destroyer
[wiki] rating: 1.0 (winrate: 51% pickrate: 13%)Brewmaster
* Outworld Destroyer's pure damage will mop up Primal Split's units very quickly.
Weaver
[wiki] rating: 1.0 (winrate: 51% pickrate: 13%)Brewmaster
* Brewmaster is slow and has low armor, making his laning stage very difficult against Geminate Attack.
* Apart from the slow moving 
Hurl Boulder, which can be disjointed, he has no control to catch Weaver.
Skywrath Mage
[wiki] rating: 1.0 (winrate: 50% pickrate: 6%)Brewmaster
* 
Ancient Seal's instant cast time will often silence Brewmaster before he can do anything.
* Brewmaster also has no defense against Skywrath Mage's massive magical damage.
Lifestealer
[wiki] rating: 1.0 (winrate: 48% pickrate: 5%)Keeper of the Light
* 
Rage allows him to dispel Blinding Light from himself.
* 
Open Wounds allows him to slow and kill Keeper of the Light.
Puck
[wiki] rating: 0.6 (winrate: 52% pickrate: 17%)Keeper of the Light
* Low health spellcasters: 
Lina, 
Witch Doctor, 
Tinker, 
Keeper of the Light, all rely heavily on their spells and are fragile heroes. They all also have avoidable spells, allowing Puck to get to them and quickly burst them down.
Oracle
[wiki] rating: 0.6 (winrate: 51% pickrate: 10%)Keeper of the Light
* Heroes with dispels: 
Legion Commander, 
Oracle, 
Slark
Storm Spirit
[wiki] rating: 0.6 (winrate: 49% pickrate: 12%)Keeper of the Light
* Heroes with teleports to escape Will-O-Wisp: Phantom Assassin, Puck, Queen of Pain, Storm Spirit
Rubick
[wiki] rating: 0.6 (winrate: 46% pickrate: 16%)Brewmaster
* Heroes with strong team-fight abilities (especially ultimates) like 
Tidehunter, 
Brewmaster, 
Death Prophet, etc.
Meepo
[wiki] rating: 0.6 (winrate: 45% pickrate: 1%)Keeper of the Light
* Heroes that can jump and kill him: 
Meepo, 
Clinkz, 
Templar Assassin
Tiny
[wiki] rating: 0.6 (winrate: 45% pickrate: 5%)Keeper of the Light
* Squishy heroes, usually supports, like 
Io, 
Ancient Apparition, Keeper of the Light etc can die instantly from Tiny's magic burst.
Juggernaut
[wiki] rating: 0.4 (winrate: 52% pickrate: 19%)Keeper of the Light
* Juggernaut's 
Healing Ward keeps his team healthy even when pushing against Keeper of the Light's 
Illuminate.
* Blade Fury can dispel 
Blinding Light, as well as dodge an incoming Illuminate. Juggernaut can attack towers during Blade Fury, so he can dodge an Illuminate without having to stop pushing.
* Should Keeper of the Light obtain 
Will-o-Wisp through purchasing an Aghanim's Scepter, Juggernaut can make quick work of Ignis Fatuus without being interrupted by its pull.
* Keeper of the Light has low health, low armor, and no natural defense against 
Blade Fury.
Keeper of the Light
* Keeper of the Light's Blinding Light makes Juggernaut miss his attacks. However, it can be dispelled easily with Blade Fury.
Legion Commander
[wiki] rating: 0.4 (winrate: 47% pickrate: 11%)Keeper of the Light
* 
Press the Attack can dispel the blind from Blinding Light from a hero.
* 
Duel can be used to instantly take Keeper of the Light out of a team-fight.
Keeper of the Light
* Heroes with abilities that blind or cause Legion Commander to miss will prevent her from winning Duels: 
Arc Warden, Keeper of the Light, 
Riki
Monkey King
[wiki] rating: -2.0 (winrate: 50% pickrate: 16%)Keeper of the Light
* Blinding Light can easily push Monkey King out of Wukong's Command, as well as blinding him.
* Will-O-Wisp destroys trees in a massive area, damaging Monkey King's mobility
* However, Keeper of the Light can be easily ganked by Monkey King during early-mid game stage.
Additional:
* Blinding Light can knock Monkey King outside of his ultimate, Wukong's Command or can generally blind him effectively.
* Will-O-Wisp stun Monkey King from Tree Dance by destroying his tree.
Brewmaster
* 
Cinder Brew and 
Drunken Brawler makes it hard for Monkey King to stack Jingu Mastery.
* 
Cyclone can remove Monkey king for 6 seconds if his allies lack dispels.
* 
Dispel Magic can dispel Jingu Mastery's bonuses.
Wraith King
[wiki] rating: -1.6 (winrate: 51% pickrate: 17%)Brewmaster
* Heroes with area dispel can kill multiple skeletons at once: Brewmaster, Oracle.
Keeper of the Light
* Wraith King's poor mobility makes him vulnerable to Illuminate.
* Blinding Light can reduce his damage output as well as his already abysmal mobility.
* Chakra Magic drains Wraith King's much-needed mana resulting in him not being able to reincarnate
Lycan
[wiki] rating: -1.6 (winrate: 54% pickrate: 3%)Brewmaster
* Brewmaster can waste a large portion of Lycan's ultimate by putting him in Cyclone.
* Lycan has no way to stop Brewmaster from using Primal Split by himself.
* Lycan's team often tries to push towers as a group, and Brewmaster excels at winning teamfights while trying to defend a tower.
Keeper of the Light
* Keeper of the Light has a blind, which causes Lycan to miss his attacks.
Enigma
[wiki] rating: -1.6 (winrate: 55% pickrate: 8%)Brewmaster
* Heroes who produce many summons will have a hard time against Storm's Dispel Magic during teamfight: 
Broodmother, 
Enigma, 
Nature's Prophet.
Keeper of the Light
* Ezalor's 
Chakra Magic will drain Enigma's mana pool rather quickly and won't let him chase or initiate with Black Hole properly.
* Will-O-Wisp will disable any close caster like Enigma, forcing him have to keep his Eidolons at maximum count and keep a safe distance.
* Illuminate can wipe the pushing Eidolons in a lane with ease, diminishing Enigma's laning presence by a lot.
Faceless Void
[wiki] rating: -1.2 (winrate: 41% pickrate: 3%)Brewmaster
* In general, Brewmaster's Cinder Brew and Thunder Clap makes him good against physical damage carries: 
Ursa, Clinkz, 
Faceless Void, 
Troll Warlord, Templar Assassin, Phantom Assassin.
Additional:
* 
Thunder Clap and Drunken Brawler prevent Faceless Void from maximizing his damage potential in fights.
* Cyclone disables Faceless Void during Chronosphere.
Keeper of the Light
* Any hero that can nullify effects of Chronosphere: (
Omniknight, 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.
Nature's Prophet
[wiki] rating: -1.2 (winrate: 44% pickrate: 5%)Keeper of the Light
* Heroes that have AoE damage: Lina, Keeper of the Light, 
Timbersaw, 
Leshrac, 
Bristleback, 
Axe
Brewmaster
* Heroes who produce many summons will have a hard time against Storm's Dispel Magic during teamfight: Broodmother, Enigma, Nature's Prophet.
Medusa
[wiki] rating: -1.0 (winrate: 45% pickrate: 2%)Keeper of the Light
* Chakra Magic can drain her current mana, draining away her effective health in a sneaky way.
* Will-O-Wisp will keep Medusa busy after she got hit by Blinding Light.
Lone Druid
[wiki] rating: -1.0 (winrate: 46% pickrate: 1%)Brewmaster
* 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.
Omniknight
[wiki] rating: -1.0 (winrate: 47% pickrate: 1%)Brewmaster
* Dispel Magic from {U:Storm} instantly removes Guardian Angel from Omniknight's allies in its radius of effect.
Elder Titan
[wiki] rating: -1.0 (winrate: 49% pickrate: 1%)Brewmaster
* {U:Earth} has passive 
Spell Immunity, allowing him to walk into the Echo Stomp radius to stun Elder Titan with his Hurl Boulder.
* {U:Storm}'s Cyclone can cancel the channeling of Echo Stomp and take Elder Titan out of the fight for {show:A|Storm|Cyclone|value2} seconds.
Ursa
[wiki] rating: -1.0 (winrate: 51% pickrate: 16%)Brewmaster
* If Ursa uses 
Enrage Brewmaster can use Cyclone to render him harmless during his ultimate.
* Brewmaster has two spells to slow down Ursa, allowing his team to kite around him easily.
Abaddon
[wiki] rating: -1.0 (winrate: 52% pickrate: 5%)Brewmaster
* Dispel Magic can remove Abaddon's 
Aphotic Shield or 
Curse of Avernus on an allied hero.
* Cyclone's lengthy duration wastes much of 
Borrowed Time's duration.
Additional:
* {U:Storm} can use Cyclone on Abaddon when he activates Borrowed Time, wasting its duration.
* Drunken Brawler and Thunder Clap hinder Abaddon from applying Curse of Avernus' silence on him.
Chaos Knight
[wiki] rating: -1.0 (winrate: 52% pickrate: 3%)Brewmaster
* 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 on, and can still deal a lot of damage to them late game, revealing the real Chaos Knight.
Ancient Apparition
[wiki] rating: -1.0 (winrate: 52% pickrate: 10%)Brewmaster
* 
Primal Split makes Brewmaster invulnerable for the duration, rendering effects of Cold Feet and Ice Blast useless.
* Dispel Magic can dispel Cold Feet from allies.
* Brewmaster can easily run Ancient Apparition down with the slow from Thunder Clap and Cinder Brew.
Beastmaster
[wiki] rating: -1.0 (winrate: 53% pickrate: 6%)Keeper of the Light
* Illuminate clears Beastmaster's summons and is effective against his push.
Sven
[wiki] rating: -0.6 (winrate: 43% pickrate: 1%)Keeper of the Light
* Keeper of the Light's AoE blind can keep Sven from landing hits.
Magnus
[wiki] rating: -0.6 (winrate: 44% pickrate: 4%)Keeper of the Light
* 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.
Terrorblade
[wiki] rating: -0.6 (winrate: 46% pickrate: 4%)Keeper of the Light
* Keeper of the Light can stall pushes with {Ability ID:Illuminate|Keeper of the Light} this makes him strong against pushing heroes: 
Terrorblade Naga siren Nature's Prophet and Anti-Mage
Techies
[wiki] rating: -0.6 (winrate: 48% pickrate: 8%)Keeper of the Light
* Heroes with flying vision such as 
Visage, 
Beastmaster, Keeper of the Light, or 
Night Stalker can scout your mines from outside their trigger radius.
Disruptor
[wiki] rating: -0.6 (winrate: 49% pickrate: 9%)Brewmaster
* Brewmaster with Primal Split
* 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
Pangolier
[wiki] rating: -0.6 (winrate: 49% pickrate: 12%)Keeper of the Light
* Certain heroes can mess up with Pangolier's positioning and timing (especially if he intends to use Rolling Thunder during combat): 
Vengeful Spirit, Keeper of the Light, Huskar, 
Dark Seer
Spirit Breaker
[wiki] rating: -0.6 (winrate: 51% pickrate: 8%)Keeper of the Light
* Heroes that punish mobile heroes: 
Bloodseeker, Keeper of the Light
Troll Warlord
[wiki] rating: -0.6 (winrate: 52% pickrate: 12%)Brewmaster
* In general, Brewmaster's Cinder Brew and Thunder Clap makes him good against physical damage carries: Ursa, Clinkz, Faceless Void, Troll Warlord, Templar Assassin, Phantom Assassin.
Broodmother
[wiki] rating: -0.6 (winrate: 53% pickrate: 2%)Brewmaster
* Heroes who produce many summons will have a hard time against Storm's Dispel Magic during teamfight: Broodmother, Enigma, Nature's Prophet.
Naga Siren
[wiki] rating: -0.6 (winrate: 54% pickrate: 2%)Keeper of the Light
* Keeper of the Light can stall pushes with {Ability ID:Illuminate|Keeper of the Light} this makes him strong against pushing heroes: Terrorblade Naga siren Nature's Prophet and Anti-Mage
Templar Assassin
[wiki] rating: -0.4 (winrate: 51% pickrate: 5%)Keeper of the Light
* Heroes that can jump and kill him: Meepo, Clinkz, Templar Assassin
Brewmaster
* The three Primal Split brewlings all attacking Templar Assassin at once will remove her 
Refraction quickly, especially with Fire's Permanent Immolation.
* Templar Assassin has no way to stop Brewmaster from using Primal Split by herself, and may get unlucky and miss her 
Meld if trying to burst him during her ally's disable.
Huskar
[wiki] rating: -0.4 (winrate: 52% pickrate: 3%)Keeper of the Light
* Vulnerable spellcasters with no escape mechanisms are easy targets for Huskar: 
Lich, 
Crystal Maiden, 
Silencer, Keeper of the Light, Venomancer, etc.
Brewmaster
* Brewmaster can use Cyclone to disable Huskar's healer for much longer than most other heroes can, to make Huskar vulnerable.
* Huskar has no way to stop Brewmaster from using Primal Split by himself, but can cut a good amount of his high health away if Huskar's team wants to burst Brewmaster down during a different disable.
Phantom Assassin
[wiki] rating: 0.0 (winrate: 45% pickrate: 16%)Keeper of the Light
* Heroes with teleports to escape Will-O-Wisp: Phantom Assassin, Puck, Queen of Pain, Storm Spirit
Brewmaster
* In general, Brewmaster's Cinder Brew and Thunder Clap makes him good against physical damage carries: Ursa, Clinkz, Faceless Void, Troll Warlord, Templar Assassin, Phantom Assassin.
Slark
[wiki] rating: 0.0 (winrate: 48% pickrate: 13%)Keeper of the Light
* Heroes with dispels: Legion Commander, Oracle, Slark
Keeper of the Light
* Melee carries during the laning phase: Sven, Slark
Anti-Mage
[wiki] rating: 0.0 (winrate: 49% pickrate: 13%)Brewmaster
* Blinking heroes like Anti-Mage or Queen of Pain can often chase down an injured Brewmaster after his ultimate expires.
Keeper of the Light
* Keeper of the Light can stall pushes with {Ability ID:Illuminate|Keeper of the Light} this makes him strong against pushing heroes: Terrorblade Naga siren Nature's Prophet and Anti-Mage
Clinkz
[wiki] rating: 0.0 (winrate: 53% pickrate: 4%)Keeper of the Light
* Heroes that can jump and kill him: Meepo, Clinkz, Templar Assassin
Brewmaster
* In general, Brewmaster's Cinder Brew and Thunder Clap makes him good against physical damage carries: Ursa, Clinkz, Faceless Void, Troll Warlord, Templar Assassin, Phantom Assassin.
Nyx Assassin
[wiki] rating: 0.0 (winrate: 54% pickrate: 7%)Keeper of the Light
* 
Mana Burn is strong against Keeper of the Light due to his high mana pool.
* 
Spiked Carapace can be used to reflect Illuminate damage and stun Keeper of the Light.
* 
Vendetta allows Nyx Assassin to follow Keeper of the Light around if he tries to split-push.
Brewmaster
* Cyclone from Storm in Primal Split can waste Nyx's Spiked Carapace, since its duration is shorter than the Cyclone's.
Keeper of the Light
* Mana Drain is very effective against heroes that have mana burn abilities such as
Anti-Mage, 
Nyx Assassin and 
Keeper of the Light.
Brewmaster
*
Hex's instant cast time will force Brewmaster into the awkward situation of needing some form of spell immunity or block to prevent being immediately hex upon blinking in, or wait until Lion has used all his crowd control before entering a fight. His direct magic burst also makes Brewmaster's Drunken Brawler worthless versus Lion.