Keeper of the Light
* 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.
Additional:
* 
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.
Abaddon
* Heroes that have long silences, such as 
Night Stalker and 
Silencer, will prevent Abaddon from saving his allies effectively and disable the active component of Borrowed Time.
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
Abaddon
* Mana Break drains Abaddon's mana, preventing him from using 
Aphotic Shield to zone out enemies in lane.
* Counterspell decreases the amount of damage received from Aphotic Shield and 
Mist Coil.
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 silences: 
Puck, 
Doom, 
Riki.
Abaddon
* Heroes with the ability to heal allies will not be able to heal heroes affected by 
Doom: 
Chen, 
Dazzle, 
Io, 
Oracle, 
Omniknight, 
Witch Doctor, 
Winter Wyvern, 
Abaddon, etc.
Additional:
* Doom will make Abaddon unable to use Mist Coil, Aphotic Shield, and the active component of Borrowed Time, also upgraded with Aghanim's Scepter can break Curse of Avernus and the passive component of Borrowed Time ,which means his allies could be easily disabled or killed.
Abaddon
* Ice Blast nullifies 
Borrowed Time's and Mist Coil's healing.
Additional:
* 
Ice Blast's nullifies Abaddon healing from Borrowed Time and Mist Coil and it is not dispelled by Aphotic Shield.
Abaddon
* Culling Blade ignores Borrowed Time should Abaddon's health falls under the threshold.
* Aphotic Shield does nothing against Berserkers Call and has to be used constantly to remove the very small mana cost of Battle Hunger in lane.
Additional:
* 
Culling Blade's instant kill is not prevented by Borrowed Time should Abaddon's health falls below the threshold.
Abaddon
* 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.
Abaddon
* Shadow Demon with an Aghanim's Scepter will use 
Demonic Purge to disable Curse of Avernus and the passive component of Borrowed Time. If this is combined with a silence, Borrowed Time will not trigger at all.
* Even without Aghanim's Scepter, he can still waste Borrowed Time with 
Disruption. Curse of Avernus fully works on illusions, turning the passive ability against him.
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
Abaddon
* 
Astral Imprisonment wastes Borrowed Time's duration.
* Outworld Destroyer's 
Sanity's Eclipse can kill Abaddon before Borrowed Time triggers due to the lack of intelligence for Abaddon.
Abaddon
* Abaddon can be killed without triggering his ultimate Borrowed Time due to the break applied by 
Sharpshooter.
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
* 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.
Abaddon
* Heroes who cannot fight back during Arena of Blood in the early and mid game: Abaddon, Anti-Mage, 
Broodmother, 
Luna, 
Sniper, Troll Warlord, 
Weaver, 
Clinkz.
Keeper of the Light
* Heroes with channeling abilities: 
Enigma, Witch Doctor, 
Crystal Maiden.
Keeper of the Light
* Heroes with hastes: 
Dark Seer, 
Lycan
Keeper of the Light
* Heroes with dispels: 
Legion Commander, Oracle, 
Slark, 
Phantom Lancer
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.
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 dispels: Legion Commander, Oracle, Slark, Phantom Lancer
Keeper of the Light
* Heroes with channeling abilities: Enigma, Witch Doctor, Crystal Maiden.
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 that can jump and kill him: 
Meepo, Clinkz, 
Templar Assassin
Keeper of the Light
* Heroes that can jump and kill him: Meepo, Clinkz, Templar Assassin
Keeper of the Light
* Heroes who have most or all their abilities (damage or disable) unable to pierce spell immunity: Keeper of the Light, 
Lina, Lion, 
Zeus.
Additional:
* 
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.
Keeper of the Light
* Heroes with silences: Puck, Doom, Riki.
Abaddon
* Lina is a common 
Eul's Scepter of Divinity carrier which can waste some duration of Borrowed Time and following up with 
Laguna Blade if timed correctly.
Abaddon
* Both Lion's 
Finger of Death and Lina's Laguna Blade have a 0.25 second delay before the damage is dealt.
Abaddon
* 
Song of the Siren completely wastes Abaddon Borrowed Time while keeping him in place.
* Naga Siren is able to simply dispel Abaddon's Curse of Avernus with 
Mirror Image before getting hit 4 times consecutively.
* Although Naga Siren's illusions can be easily destroyed by Aphotic Shield, Naga Siren can resolve that issue easily by purchasing 
Heart of Tarrasque to drastically increase her durability. Plus, the said item makes Naga Siren harder to be distinguished from her illusions.
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
* Large area-of-effect with delay or require channeling: Enigma, Crystal Maiden, 
Invoker, 
Shadow Fiend, 
Pugna, Keeper of the Light, 
Dawnbreaker.
Additional:
* 
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.
Abaddon
* 
Nyx Assassin might not kill Abaddon with his nuke, but a support Abaddon will struggle to protect an ally from him.
Abaddon
* 
Impale and Spiked Carapace stun can be instantly dispelled by Aphotic Shield.
* Abaddon can use Borrowed Time and easily heal for the duration of Borrowed Time by Nyx's burst damage.
Keeper of the Light
* Illuminate clears Beastmaster's summons and is effective against his push.
Abaddon
* Aphotic Shield effectively nullifies Primal Roar's single-target initiation on allies.
* Even being initiated by Primal Roar, Borrowed Time can make Abaddon extremely difficult to kill.
Additional:
* 
Primal Roar can be instantly dispelled by Aphotic Shield.
* The debuffs from 
Wild Axes and 
Poison from 
Call of the Wild: Boar can also be dispelled by Aphotic Shield.
Keeper of the Light
* Heroes with summons/illusions/neutral creep armies: 
Beastmaster, Chen, Naga Siren
Abaddon
* Aphotic Shield can nullify Chen's combo, while clearing Chen's creeps simultaneously.
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.
Abaddon
* Mist Coil and Aphotic Shield enable Abaddon to keep an ally alive during Chronosphere.
* Borrowed Time prevents Faceless Void from killing Abaddon during his Chronosphere.
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.
Abaddon
* Borrowed Time can give Abaddon a second chance after a Black Hole combo.
* Aphotic Shield can be used to save allies or Abaddon himself from Malefice.
* Abaddon can easily heal himself as well as his allies during a team fight, especially with Aghanim's Scepter upgraded Borrowed Time.
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.
Abaddon
* Any hero who can survive Magnus's initiations and manfight him: Huskar, Faceless Void, Weaver, Abaddon, Troll Warlord, Alchemist, 
Dragon Knight, Night Stalker, 
Viper.
Abaddon
* Aphotic Shield is a strong dispel, meaning it can save allies from Earth Spirit's stun, slow, silence, and Magnetize.
* Borrowed Time makes it nearly impossible for Earth Spirit to kill Abaddon.
Abaddon
* Aphotic Shield applies a strong dispel on the allied target and can be used to remove both Fiend's Grip & Nightmare.
* Borrowed Time applies a strong dispel on Abaddon and can instantly remove both Fiend's Grip & Nightmare when activated.
* Bane, when caught by Curse of Avernus will struggle to escape because of his innately low mobility.
Additional:
* 
Nightmare and 
Fiend's Grip can be instantly dispelled by Aphotic Shield.
* Bane lacks mobility, therefore becoming helpless when silenced by Curse of Avernus.
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.
Abaddon
* Aphotic Shield prevents damage and dispels the slow from Snapfire's 
Mortimer Kisses.
* Borrowed Time allows Abaddon to gain HP during Snapfire's Mortimer Kisses.
Abaddon
* Abaddon can activate Borrowed Time to dispel Dismember; breaking the disable and potentially allowing Abaddon to escape.
* Aphotic Shield can be cast on an ally to dispel the stun of Dismember, which can make kills difficult to secure, given that Dismember is Pudge's only reliable disable.
* Pudge lacks a mobility without a 
Blink Dagger, causing him to be easily chased with Curse of Avernus. The silence also prevents him from toggling off his Rot.
Abaddon
* Borrowed Time mitigates the damage by Pierce the Veil for most of its duration.
* Muerta has no control over Gunslinger, making her one of the best heroes for Abaddon to regenerate from via Borrowed Time.
Abaddon
* 
Exorcism will continuously heal Abaddon under Borrowed Time, and cannot be turned off.
* {Ability ID:Spirit Siphon|Death Prophet} will continuously heal Abaddon under Borrowed Time, for a percentage of his maximum health.
Abaddon
* Aphotic Shield makes it less likely for allies to be killed by mines.
* Because they explode in very short intervals, a stack of 
Remote Mines will always trigger Borrowed Time, making them impossible to kill Abaddon unless his resistances are lowered enough or Abaddon is affected by Break.
* Abaddon can easily dispel the long-lasting root of 
Stasis Trap on himself and on an ally, while at the same also providing protection against the other mines' damage.
Additional:
* Borrowed Time's automatic activation will help Abaddon survive a field of Proximity Mines or a Blast Off combo. However, the damage from a single mine can kill him if his HP is low enough.
* Aphotic Shield's can easily break Techies' Etheral Blade combo.
Abaddon
* Aphotic Shield dispels Thunder Strike.
* Mist Coil can be used to heal an ally trapped by Static Storm-Kinetic Field combo.
* Borrowed Time makes Abaddon nearly impossible to gank.
Abaddon
* Abaddon can cast Aphotic Shield on any of his allies to immediately dispel Corrosive Haze and/or the stun and the slow components of Slithereen Crush.
* All of Slardar's debuffs are also removed if Abaddon's Borrowed Time triggers.
Abaddon
* Aphotic Shield removes silences, slows and stuns, possibly foiling a full-duration Mystic Flare.
* Borrowed Time makes it impossible to burst Abaddon down, even healing him up due to Mystic Flare's damage.
Abaddon
* Borrowed Time & Aphotic Shield can dispel Venomous Gale and Poison Sting.
Abaddon
* Aphotic Shield and Borrowed Time can both dispel Flaming Lasso.
Additional:
* 
Sticky Napalm, 
Flaming Lasso, and 
Flamebreak can all be instantly dispelled by Aphotic Shield.
* 
Firefly will continuously heal Abaddon under Borrowed Time.
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.
Abaddon
* Abaddon could punish Chaos Knight for using his Phantasm and Reality Rift combo on him with 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, effectively reducing the amount of targets Chaos Knight can threaten by 1 for the entire game.
Abaddon
* Abaddon can remove Sacred Arrow's stun from his teammates with Aphotic Shield, or remove it from himself with Borrowed Time.
* Borrowed Time makes Abaddon almost impossible to burst down with Mirana's Aghanim's Scepter combo.
Additional:
* 
Sacred Arrow can be instantly dispelled by Aphotic Shield.
Abaddon
* Heroes that can purge his slow and disables are very difficult to go on and their team: Abaddon, Oracle.
Keeper of the Light
* Keeper of the Light's AoE blind can keep Sven from landing hits.
Keeper of the Light
* Heroes that punish mobile heroes: 
Bloodseeker, Keeper of the Light, Kunkka, 
Disruptor.
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
Abaddon
* Heroes that can deny Slark early kills will prevent him from snowballing: Dazzle, Abaddon.
Abaddon
* Abaddon with Aphotic Shield and Borrowed Time
* Heroes that can remove the Track debuff with their skills:
* Abaddon with Aphotic Shield and Borrowed Time
* Huskar with 
Life Break
* 
Juggernaut with 
Blade Fury
* Legion Commander with 
Press the Attack
* 
Lifestealer with Rage and 
Infest
* Naga Siren with Mirror Image
* Omniknight with 
Heavenly Grace
* Oracle with 
Fortune's End and 
False Promise
* Phantom Lancer with 
Doppelganger
* Slark with 
Dark Pact
* 
Ursa with 
Enrage
* Weaver with 
Time Lapse
* Tidehunter with 
Kraken Shell when damage received reaches the threshold.
Abaddon
* Omniknight can dispel Hex or Shackles with Heavenly Grace. He can also heal teammates who you disabled. The same goes for Abaddon's Aphotic Shield.
Abaddon
* Clockwerk lacks burst damage, and that makes him vulnerable to heroes who can recover themselves and turn the fight around to their advantage after Clockwerk finishes his initiation. Additionally, Clockwerk hates buying 
Dagon and 
Ethereal Blade, which are the only itmes that can help him deal with heroes who can recover themselves and turn the fight around to their advantage: Faceless Void, Terrorblade, Ursa, Weaver, Broodmother, Slark, Abaddon, Wraith King, Lifestealer.
Abaddon
* Heroes that deal damage over time will also fail to bring down Abaddon and his allies, such as Huskar, Venomancer, or Phoenix.
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
Abaddon
* In general, heroes that deal burst in multiple instances will trigger Borrowed Time and heal Abaddon for a large amount, such as 
Skywrath Mage, 
Techies, Juggernaut, Shadow Shaman, or 
Ogre Magi.
Abaddon
* Heroes who possess abilities that can save targets from being killed by Reaper's Scythe: Abaddon, 
Bane, Outworld Destroyer, Shadow Demon, Omniknight, etc.
Additional:
* If he isn't silenced, Abaddon can use Borrowed Time to escape 
Reaper's Scythe during the delay.
Keeper of the Light
* Heroes that have AoE damage: Lina, Keeper of the Light, 
Timbersaw, 
Leshrac, 
Bristleback, 
Axe.
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.
Abaddon
* Every hero that can withstand or prevent Eclipse at level 7: Juggernaut, Riki, 
Clockwerk, 
Drow Ranger, Abaddon, Faceless Void, Weaver, Outworld Destroyer.
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
Abaddon
* If he isn't broken (break), Abaddon can use Borrowed Time to waste Legion Commander's Duel, As Borrowed Time has a shorter cooldown, Legion Commander can't win duels, effectively reducing her targets by one, Duel also means that Borrowed Time heals Abaddon for the duration of the duel, as Legion can't stop attacking.
Additional:
* 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.
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.
Abaddon
* Huskar's damage over time gives Abaddon the opportunity to shield and heal his allies.
* Borrowed Time also makes Abaddon a hard support to gank, thus negating Huskar's early game dominance.
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.
Abaddon
* Aphotic Shield applies strong dispel on targeted allies, while Borrowed Time does the same on Abaddon himself upon both casts (manually or automatically), removing disables, such as 
Earth Spike and 
Hex.
* Abaddon may offer survivability to Lion's nuke power by shielding and healing allies and himself.
* Lack of inner escape and defensive mechanisms increases Curse of Avernus effectiveness, since it slows per stack (applied upon auto attacking), and silences when it reaches the maximum stack.
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.
Abaddon
* In general, heroes that deal burst in multiple instances will trigger Borrowed Time and heal Abaddon for a large amount, such as Skywrath Mage, Techies, Juggernaut, Shadow Shaman, or Ogre Magi.
Abaddon
* Reflection will cause Abaddon to be afflicted by his own Curse of Avernus, silencing and slowing him. The reflection is also hard to avoid, as it cannot be killed, only dispelled.
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
Abaddon
* Heroes who can negate effects of Sunder: Faceless Void's 
Time Walk, Weaver's Time Lapse, Broodmother's 
Insatiable Hunger, Abaddon's Borrowed Time and Troll Warlord's 
Battle Trance can nullify Sunder.
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.
Keeper of the Light
* Heroes who are strong against mobile heroes: Disruptor, Bloodseeker, Kunkka, Keeper of the Light.
Abaddon
* Because 
Poison Attack has almost no cooldown, Aphotic Shield is ineffective as a hard dispel.
* 
Viper Strike can prevent Borrowed Time from activating passively and block Curse of Avernus.
Additional:
* Because Poison Attack has almost no cooldown, Aphotic Shield is ineffective as a hard dispel.
* Viper Strike can prevent Borrowed Time from activating passively and block Curse of Avernus.
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
* 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
* 
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.
Abaddon
* Borrowed Time makes Abaddon nearly impossible to gank.
* Aphotic Shield and Mist Coil prevents Bloodseeker from gaining his Thirst bonuses.
Additional:
* If Rupture is used on Abaddon, Abaddon can use Borrowed Time and easily heal for the duration of Borrowed Time by simply moving.
Keeper of the Light
* Heroes with hastes: Dark Seer, Lycan
Keeper of the Light
* Keeper of the Light has a blind, which causes Lycan to miss his attacks.
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.
Abaddon
* Heroes that have long silences, such as
Night Stalker and 
Silencer, will prevent Abaddon from saving his allies effectively and disable the active component of Borrowed Time.