Keeper of the Light
* 
Blood Rite makes Ezalor chose between getting off Illuminate or getting silenced for a while, as Illuminate is a channeled ability.
* Blood Rite's silence can completely take Ezalor out of a teamfight, as he relies on his abilities to be useful.
* Keeper of the Light's only mobility source, his high movement speed (via his high base movement speed and through spirit form), is entirely countered by 
Rupture.
Marci
* Rupture ruins her only movement ability, Rebound. Combined with its high movement speed and her being unable to interrupt it once its cast, using it under the effects of Rupture will surely deal incredibly immutable damage, if not kill her.
* As a Strength hero, Marci naturally has high HP. Rupture's initial damage uses her high HP as a catalyst to deal damage depending on her current health, dealing a good amount of damage if she's full HP or forcing her to stop if she's low.
* With 
Aghanim's Shard, 
Bloodrage will now deal pure damage and lifesteal based on the opponent's max health. Her high HP as a Strength hero ensures that Bloodseeker will always deal significant attack damage and sustain himself a lot whenever he attacks Marci.
* If Marci doesn't build 
Black King Bar, Bloodseeker's Blood Rite will prevent her from using all of her spells which she relies quite heavily on. Her only dispel is tied to Sidekick with level 25 left talent.
Keeper of the Light
* Heroes with dispels: 
Legion Commander, 
Oracle, 
Slark, 
Phantom Lancer
Marci
* 
Fortune's End dispells Marci's 
Sidekick, removing additional damage and lifesteal.
* 
Fate's Edict disarms Marci, preventing her from attacking with 
Unleash. Also it is useful against Marci or her ally affected by Sidekick.
* 
False Promise is a great tool to save an ally focused by Marci.
Keeper of the Light
* Being an intelligence caster hero, Ezalor usually has a high mana pool and low health and armor, making him a prime target for 
Mana Void
* Ezalor's Illuminate damage and Solar Bind's magic resistance reduction are greatly reduced thanks to 
Counterspell. Counterspell can also block and reflect Solar Bind if timed properly.
* Anti-Mage usually is not hampered by Solar Bind or Will-O-Wisp thanks to 
Blink.
* However, despite all of this, if Keeper of the Light is played carefully and tops off his team's mana at all times, Anti Mage will not be able to get off a good Mana Void.
* By the same token once Keeper of the Light gets a 
Octarine Core, he can spam Charka Magic to keep his own mana ful
Marci
* Counterspell will reflects from Dispose. Counterspell timing well can not throw from Dispose endured position and Dispose will blocked.
Keeper of the Light
* 
Keeper of the Light can stall pushes with 
Illuminate. This makes him strong against pushing heroes: 
Terrorblade 
Naga siren 
Nature's Prophet and 
Anti-Mage
Keeper of the Light
* Heroes with teleports to escape Solar Blind and Will-O-Wisp: 
Phantom Assassin, 
Puck, 
Queen of Pain, 
Storm Spirit
Marci
* Heroes that can reliably kite out Dispose, Unleash and dodge Rebound, like 
Ember Spirit, 
Void Spirit, Storm Spirit, Anti-Mage, 
Faceless Void, Puck or always build items like 
Blink Dagger and 
Force Staff.
Keeper of the Light
* 
Finger of Death can instantly shred many targets, especially fragile Heroes like Keeper of the Light, 
Ancient Apparition or 
Bounty Hunter.
Marci
* Heroes that can keep Marci for a long time in one place so she can't pursue her targets, like 
Bane, 
Lion, 
Shadow Shaman, 
Invoker, 
Disruptor and 
Kunkka.
Marci
* Unleash ensures that Axe's 
Counter Helix procs many times, even if he is stunned by Dispose.
* Aghanim's Shard allows Counter Helix to reduce the attack damage of anyone it strikes. Combined with Unleash causing to proc frequently, Marci will not be dealing significant damage as she attacks Axe over time.
* Axe doesn't worry about the damage from Unleash if he activates 
Berserker's Call beforehand. If he had activated 
Blade Mail or 
Mjollnir (or even both) as Marci attacks him, he will turn Unleash's high attack speed and damage against her.
* Usually, Axe would prefer to jump on his opponent to be more effective. Rebound does Axe a favor, bringing Marci within his most effective range.
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, as it allows Night Stalker to jump the backline and quickly kill the squishy Ezalor, especially when combined with the slow from 
Void.
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.
Marci
* Warlock has strong counter initiation which reduces Marci's effectiveness throughout the game.
* 
Fatal Bonds cancels Blink Dagger, which means Marci can move in and out of fights less effectively.
* 
Chaotic Offering paired with 
Upheaval provides a ministun, a movement slow and paired with Fatal Bonds has the potential to deal a lot of damage to Marci while she jumps on a target. The ministun also means that Marci will have a harder time casting Rebound. If Warlock does build Aghanim's Scepter and 
Refresher Orb, the physical damage from Golems will overwhelm Marci, especially when played as a support.
Marci
* 
Spirit Siphon exploits her naturally high HP to deal a good amount of DPS. She may break the link with Rebound, but 
Silence covers that problem.
* Marci's poor armor makes her vulnerable to 
Exorcism.
Marci
* Marci's Dispose is blocked by 
Linken's Sphere which is a common item for Weaver.
* 
Shukuchi allows Weaver to escape from 
Rebound slow.
* 
The swarm beetle require 4 hits to kill. Weaver can use it on her when she use Unleash. This give Marci a hard choice: ignore The swarm and her armor keep decreasing or kill the beetle and wasting 4 attacks of Unleash.
Marci
* 
Bramble Maze will very likely catch Marci midair, disabling Marci's chasing/fleeing ability.
* 
Shadow Realm prevents Marci from bursting Willow down since she relies on physical attacks and unit target spells. With Aghanim's Scepter, Willow can hit Marci while Marci can't hit Willow.
* 
Bedlam and 
Eul's Scepter of Divinity allows Willow to manfight if Marci initiates with Rebound.
* 
Terrorize and 
Cursed Crown combo can waste Marci's ultimate for almost half of its duration.
Keeper of the Light
* 
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.
* Keeper of the Light is very squishy and will very quickly die to Vendetta and it's followup abilities.
Keeper of the Light
* Being a cast-oriented hero, Ezalor will suffer from all of Silencer's abilities.
* 
Global Silence is a guaranteed lengthy silence which will render Ezalor useless in a teamfight.
* 
Arcane Curse and 
Last Word are good against any caster, since they are extremely potent.
* However, it should be worth mentioning that a smart Ezalor will buy Eul's Scepter of Divinity to dispel Silencer's abilities. Combined with the level 20 talent (Chakra Magic applies a basic dispel), Ezalor can purge Silencer's abilities off allies and himself alike.
Keeper of the Light
* Pugna easily copes on the line with the Keeper of the Light push with his 
Nether Blast, and in addition to 
Nether Ward, the Keeper of the Light is not able to throw Illuminate on creeps for a long time, so Pugna earns more gold and a level on the line
Additional:
* Pugna easily copes on the line with the Keeper of the Light push with his Nether Blast, and in addition to Nether Ward, the Keeper of the Light is not able to throw Illuminate on creeps for a long time, so Pugna earns more gold and a level on the line
Marci
* 
Death Pulse and 
Ghost Shroud very effective against her physical damage.
* 
Heartstopper Aura and 
Reaper's Scythe are very effective against tanky Strength hero Marci.
Keeper of the Light
* Heroes with hastes: 
Dark Seer, 
Lycan
Marci
* 
Howl reduces a good chunk of Marci's attack damage that she relies heavily on, and the armor reduction works better on her because of her low armor.
* 
Shapeshift renders Lycan immune to slow from Rebound and Unleash.
Keeper of the Light
* Keeper of the Light has a blind, which causes Lycan to miss his attacks.
Marci
* Heroes that reduce the damage that Marci can deal during her ultimate, like 
Razor, 
Rubick, Bane, 
Dragon Knight and 
Underlord.
Marci
* Heroes that can reliably kite out Dispose, Unleash and dodge Rebound, like Ember Spirit, Void Spirit, Storm Spirit, Anti-Mage, Faceless Void, Puck or always build items like Blink Dagger and Force Staff.
Marci
* Heroes that can keep Marci for a long time in one place so she can't pursue her targets, like Bane, Lion, Shadow Shaman, Invoker, Disruptor and Kunkka.
Additional:
* Shadow Shaman can provide an excellent counter-initiation against her Rebound. His abilities can shut down any of her tower dive attempts in the laning phase.
* Shackles keeps Marci stunned for an extended time, wasting her ultimate. A combo with Mass Serpent Ward only makes things worse for her, as her armor is low.
Keeper of the Light
* Heroes with hastes: Dark Seer, Lycan
Keeper of the Light
* With 
Bloodthorn, Clinkz becomes a strong counter to heroes who rely on evasion and blind such as 
Windranger, Phantom Assassin, 
Troll Warlord and Keeper of the Light.
Marci
* Heroes that can keep Marci for a long time in one place so she can't pursue her targets, like Bane, Lion, Shadow Shaman, Invoker, Disruptor and Kunkka.
Keeper of the Light
* Heroes that can jump and kill him: 
Meepo, 
Clinkz, 
Templar Assassin
Marci
* Heroes that can keep Marci for a long time in one place so she can't pursue her targets, like Bane, Lion, Shadow Shaman, Invoker, Disruptor and Kunkka.
Marci
* Heroes that can reliably kite out Dispose, Unleash and dodge Rebound, like Ember Spirit, Void Spirit, Storm Spirit, Anti-Mage, Faceless Void, Puck or always build items like Blink Dagger and Force Staff.
Marci
* Heroes that can keep Marci for a long time in one place so she can't pursue her targets, like Bane, Lion, Shadow Shaman, Invoker, Disruptor and Kunkka.
Keeper of the Light
* Heroes with channeling abilities: 
Enigma, 
Witch Doctor, 
Crystal Maiden.
Keeper of the Light
* Jakiro's reliance on his abilities can cause struggles for heroes who rely on evasion or blinds to get upper hand: Phantom Assassin, Windranger, 
Riki, Troll Warlord, Keeper of the Light.
Marci
* Heroes that reduce the damage that Marci can deal during her ultimate, like Razor, Rubick, Bane, Dragon Knight and Underlord.
Keeper of the Light
* Heroes with silences: Puck, 
Doom, Riki.
Keeper of the Light
* Heroes with teleports to escape Solar Blind and Will-O-Wisp: Phantom Assassin, Puck, Queen of Pain, Storm Spirit
Keeper of the Light
* Any hero who lanes very poorly will struggle with Primal Beast's potential snowball in the very early levels, like Keeper of the Light, 
Luna, Templar Assassin...
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.
Keeper of the Light
* Heroes with channeling abilities: Enigma, Witch Doctor, Crystal Maiden.
Keeper of the Light
* Squishy heroes, usually supports, like Lion, Ancient Apparition, Keeper of the Light etc can die quickly to Tiny's magic burst.
Keeper of the Light
* Heroes with silences: Puck, Doom, Riki.
Marci
* Heroes that can reliably kite out Dispose, Unleash and dodge Rebound, like Ember Spirit, Void Spirit, Storm Spirit, Anti-Mage, Faceless Void, Puck or always build items like Blink Dagger and Force Staff.
Keeper of the Light
* Heroes who are strong against mobile heroes: Disruptor, 
Bloodseeker, Kunkka, Keeper of the Light.
Marci
* Heroes that reduce the damage that Marci can deal during her ultimate, like Razor, Rubick, Bane, Dragon Knight and Underlord.
Marci
* Heroes that can keep Marci for a long time in one place so she can't pursue her targets, like Bane, Lion, Shadow Shaman, Invoker, Disruptor and Kunkka.
Keeper of the Light
* Heroes that can jump and kill him: Meepo, Clinkz, Templar Assassin
Keeper of the Light
* Heroes with silences: Puck, Doom, Riki.
Keeper of the Light
* Heroes with dispels: Legion Commander, Oracle, Slark, Phantom Lancer
Keeper of the Light
* 
Press the Attack can dispel Blinding Light or Solar Bind 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, 
Tinker
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.
Additional:
* Blade Fury allows him to be immune to all of Ezalor's abilities.
* Healing Ward heals his entire team, mitigating Ezalor's weak magical burst damage.
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.
Marci
* Pangolier's 
Lucky shot disarms her if procs making Unleash useless.
* 
Swashbuckle have a lower cooldown than Rebound so Pangolier can out maneuver her quite easily.
Additional:
* Pangolier's Lucky Shot disarms her if it procs, making Unleash useless.
* Swashbuckle will easily burn away Marci's already low mana pool with 
Diffusal Blade, an item commonly built on Pangolier.
* Swashbuckle's cooldown is shorter than Rebound, making it easy for Pangolier to outmaneuver her.
* Marci will get stunned if she tries to use Rebound while Pangolier is using Rolling Thunder, somewhat hindering her mobility in teamfights.
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
Keeper of the Light
* Keeper of the Light can stall pushes with Illuminate. This makes him strong against pushing heroes: Terrorblade Naga siren Nature's Prophet and Anti-Mage
Marci
* 
Sprout can't stop her to Rebound.
* Treants can be used as targets for Rebound and Dispose as well.
Keeper of the Light
* Illuminate clears Beastmaster's summons and is effective against his push.
Keeper of the Light
* Blinding Light can knock Monkey King outside of his ultimate, Wukong's Command and can blind him.
* Will-O-Wisp will stun Monkey King from Tree Dance by destroying his tree.
Additional:
* Blinding Light can easily push Monkey King out of Wukong's Command, as well as blinding him.
* Monkey King is vulnerable to burst damage, 
Solar Bind makes him more so
* However, Keeper of the Light can be easily ganked by Monkey King during early-mid game stage.
Marci
* 
Untouchable doesn't work against Unleash, as Marci gains 1000+ attack speed for the fury combo.
* Enchantress' low health makes her a fragile target for Marci's damage blasts.
* Marci can use Rebound on one of her enchanted creeps to easily reach the Enchantress and negate the bonus damage dealt by her 
Impetus. It helps that most of her best creeps have a low attack range, creating a makeshift bridge towards their master.
Marci
* Rebound allows her to jump in or out of the 
Arena Of Blood. She can save her allies from the Arena with Dispose as well.
Marci
* Marci on the midlane will win the laning phase against Zeus almost every time, as her powerspike at level 6 will decimate Zeus' low health pool and force him to stay far back.
* Even before level 6, Dispose and Sidekick can easily take half of Zeus' health if he is in range of Dispose.
Marci
* Marci can destroy 
Supernova by herself with Unleash at any stage of the game.
* Phoenix is squishy hero with low armor and is very vulnerable for Rebound and Sidekick at the laning stage.
Keeper of the Light
* The Keeper of the Light easily farms on the line against the Viper, due to the fact that it has a long-range Illuminate, and the Viper, in turn, cannot use its advantage of dominance on the center line, due to the fact that it does not reach the Keeper of the Light
Additional:
* The Keeper of the Light easily farms on the line against the Viper, due to the fact that it has a long-range Illuminate, and the Viper, in turn, cannot use its advantage of dominance on the center line, due to the fact that it does not reach the Keeper of the Light
Keeper of the Light
* Illuminate wipes out Broodmother's spiders and prevents her from pushing the lane. It also gives vision to reveal where broodmother is hiding in the trees.
Keeper of the Light
* Heroes with summons/illusions/neutral creep armies: 
Beastmaster, 
Chen, Naga Siren
Keeper of the Light
* Keeper of the Light can stall pushes with Illuminate. This makes him strong against pushing heroes: Terrorblade Naga siren Nature's Prophet and Anti-Mage
Keeper of the Light
* Keeper of the Light can stall pushes with Illuminate. This makes him strong against pushing heroes: Terrorblade Naga siren Nature's Prophet and Anti-Mage
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, 
Medusa, 
Dawnbreaker.
Marci
* Marci can be effective against vulnerable squishy heroes that cannot deal with heroes that jump onto them - 
Sniper, 
Drow Ranger, Lina, Rubick, etc.
Marci
* Marci can be effective against vulnerable squishy heroes that cannot deal with heroes that jump onto them - Sniper, Drow Ranger, Lina, Rubick, etc.
Keeper of the Light
* Heroes that punish mobile heroes: Bloodseeker, Keeper of the Light, Kunkka, Disruptor.
Marci
* Marci can be effective against vulnerable squishy heroes that cannot deal with heroes that jump onto them - Sniper, Drow Ranger, Lina, Rubick, etc.
Keeper of the Light
* Melee carries during the laning phase: Sven, Slark
Keeper of the Light
* Heroes which rely exclusively on right clicks will struggle somewhat against Blinding Light: Phantom Assassin, Wraith King, Medusa
Keeper of the Light
* Heroes with extremely slow movement speed will cripple against Solar Bind: Medusa, 
Viper
Additional:
* Will-O-Wisp will keep Medusa busy after she got hit by Blinding Light.
Keeper of the Light
* Heroes with channeling abilities: Enigma, Witch Doctor, Crystal Maiden.
Keeper of the Light
* Illuminate can wipe the pushing Eidolons in a lane with ease, diminishing Enigma's laning presence by a lot.
* Solar Bind will severely slow down Enigma and make him more vulnerable to magical damage more he moves for it's duration.
* However, Keeper of the Light does not have any way to cancel 
Black Hole outside from Will-O-Wisp provided by Aghanim's Scepter.
Marci
* Heroes that reduce the damage that Marci can deal during her ultimate, like Razor, Rubick, Bane, Dragon Knight and Underlord.
Marci
* Marci can be effective against vulnerable squishy heroes that cannot deal with heroes that jump onto them - Sniper, Drow Ranger, Lina, Rubick, etc.
Marci
* Heroes that can reliably kite out Dispose, Unleash and dodge Rebound, like Ember Spirit, Void Spirit, Storm Spirit, Anti-Mage, Faceless Void, Puck or always build items like Blink Dagger and Force Staff.
Keeper of the Light
* Any hero that can nullify effects of Chronosphere: (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.
Keeper of the Light
* Heroes with dispels: Legion Commander, Oracle, Slark, Phantom Lancer
Keeper of the Light
* Melee carries during the laning phase: Sven, Slark
Keeper of the Light
* Heroes with teleports to escape Solar Blind and Will-O-Wisp: Phantom Assassin, Puck, Queen of Pain, Storm Spirit
Keeper of the Light
* Heroes which rely exclusively on right clicks will struggle somewhat against Blinding Light: Phantom Assassin, Wraith King, Medusa
Keeper of the Light
*
Rage allows him to be immune to all of Ezalor's abilities. Also, the increased movement speed combined with the slow from 
Ghoul Frenzy and the squishy nature of Ezalor allows Lifestealer to take him down very quickly.
Marci
* Lifestealer's
Rage renders him immune to all of Marci's disables and magic damage for a good duration.
Feast deals bonus damage based on the enemy's max health and heals for the same amount. As a tanky Strength hero, Marci's own strength will be her undoing as well.
* His passive