Keeper of the Light
* Heroes with dispels: 
Legion Commander, 
Oracle, 
Slark, 
Phantom Lancer
Skywrath Mage
* Fate Edict can completely negate Skywrath Mage's heavy magic damage.
* Fortune End dispels 
Ancient Seal.
Keeper of the Light
* Heroes that can jump and kill him: 
Meepo, 
Clinkz, 
Templar Assassin
Skywrath Mage
* Templar Assassin easily withstands all the damage from Skyrwrath Mage, thanks to its first ability 
Refraction. In addition, Templar Assassin can kill Skywrath Mage with a single hit from under the second ability 
Meld.
Additional:
* Templar Assassin easily withstands all the damage from Skyrwrath Mage, thanks to its first ability Refraction. In addition, Templar Assassin can kill Skywrath Mage with a single hit from under the second ability Meld.
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.
Skywrath Mage
* Heroes with silence such as 
Riki, 
Silencer, or 
Night Stalker prevents Skywrath Mage from using his spells.
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.
Skywrath Mage
* Slow-moving projectiles: 
Skywrath Mage, 
Tinker, 
Necrophos
Additional:
* Skywrath Mage's low health makes him rather easy prey for Nyx Assassin and his lack of armor generally means he'll take the full brunt of a Vendetta strike.
* 
Mind Flare turns Skywrath Mage's high intelligence growth against him and deals heavy damage.
* Spiked Carapace gives Nyx some degree of protection against Skywrath's spells.
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.
Skywrath Mage
* Heroes with silence such as Riki, Silencer, or Night Stalker prevents Skywrath Mage from using his spells.
Keeper of the Light
* Heroes with silences: 
Puck, 
Doom, Riki.
Skywrath Mage
* Due to his low health and armor, Riki can easily kill Skywrath Mage.
* Smoke Screen prevents Skywrath from using all of his abilities, as he does not tend to buy 
Black King Bar.
* However, Skywrath Mage can easily kill Riki if he manages to root Riki with Rod of Atos or Gleipnir, followed by Dust of Appearance, Ancient Seal and Mystic Flare.
Keeper of the Light
* Heroes that can jump and kill him: Meepo, Clinkz, Templar Assassin
Skywrath Mage
* Skywrath Mage's abilities are single targeted and he can't use Mystic Flare to its fullest potential, since all Meepos spread the damage between them. He also has no disables to prevent Meepo from Poofing to another one (unless he can get Ancient Seal off first).
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.
Skywrath Mage
* Skywrath's pitiful defences also make him easy meat to heroes with high burst like 
Juggernaut, 
Lion, or 
Phantom Assassin, the latter occasionally downing a support Skywrath in a single 
Stifling Dagger.
Keeper of the Light
* Heroes with dispels: Legion Commander, Oracle, Slark, Phantom Lancer
Skywrath Mage
* Skywrath Mage also has a terrible time fighting against anything that isn't a hero. 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.
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.
Skywrath Mage
* Skywrath Mage's armor and agility gain is very low, so when Huskar's 
Burning Spears stack they can take him down very quickly at any point of the game.
* 
Berserker's Blood grants bonuses as Huskar uses Burning Spears to harass Skywrath Mage, granting him attack speed, magic resistance, and strength as health regen, making it possible that Huskar can harass Skywrath Mage out of lane and sustain through his magic burst through staying injured throughout lane, or even the game.
* 
Life Break allows Huskar to jump onto Skywrath Mage, closing the distance between them and busting him down so he cannot run. This can be combed with 
Inner Fire, adding a movement speed slow if Aghanim's Shard is applied so Skywrath Mage cannot escape.
Skywrath Mage
* Heroes with high magical burst can easily kill Huskar when he is at low health: Lion, 
Lina, Skywrath Mage
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.
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.
Skywrath Mage
* Skywrath's pitiful defences also make him easy meat to heroes with high burst like Juggernaut, Lion, or Phantom Assassin, the latter occasionally downing a support Skywrath in a single Stifling Dagger.
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.
Skywrath Mage
* Outworld Destroyer can steal more mana with 
Astral Imprisonment from Skywrath Mage with 
Shield of the Scion (granted by 
Aghanim's Shard). Shield of the Scion grants Skywrath Mage bonus intelligence every time he deals magic damage to an enemy hero with his abilities. The higher his intelligence, the larger his mana pool. Since Astral Imprisonment steals based on the target's max mana, Outworld Destroyer can steal much more mana from Skywrath Mage.
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.
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
Skywrath Mage
* 
Mana Break drains Skywrath Mage of his mana, slowing him and dealing bonus damage while rendering him unable to cast his spells.
* Blink makes it incredibly easy for Anti-Mage to close the gap between himself Skywrath Mage to right-click him down. He can also use Blink to get away and escape into fog of war.
* Anti-Mage passively reduces enemy spell damage with Counterspell, and can activate the ability to block and send back Skywrath's Ancient Seal or Arcane Bolt, causing him to silence himself or deal massive damage to himself.
* Skywrath Mage's large mana-costs makes him an easy target for Mana Void.
* Anti-Mage often builds Black King Bar and 
Manta Style which can dispel Ancient Seal and Concussive Shot.
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
Skywrath Mage
* Heroes with abilities or items that can silence or disable Anti-Mage for long periods of time will prevent him from Blinking away: Lion, Silencer, 
Shadow Shaman, 
Grimstroke, 
Witch Doctor, Riki, 
Faceless Void, Skywrath Mage, Puck.
Keeper of the Light
* Heroes with hastes: 
Dark Seer, Lycan
Skywrath Mage
* Fragile heroes: Bounty Hunter has decent nuking capabilities with Shiruken Toss and Jinada thus making fragile heroes easy picks for ganking. Few examples of such heroes are:Crystal Maiden, 
Pugna, Skywrath Mage, 
Io, Witch Doctor, etc.
Skywrath Mage
* 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.
Additional:
* 
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.
Keeper of the Light
* Heroes with hastes: Dark Seer, Lycan
Skywrath Mage
* Once you get a Black King Bar, squishy spellcasters like 
Zeus, Skywrath Mage and others will be probably easy to deal with.
Keeper of the Light
* Keeper of the Light has a blind, which causes Lycan to miss his attacks.
Keeper of the Light
* Heroes with channeling abilities: 
Enigma, Witch Doctor, Crystal Maiden.
Keeper of the Light
* Heroes with channeling abilities: Enigma, Witch Doctor, Crystal Maiden.
Skywrath Mage
* Skywrath Mage also has a terrible time fighting against anything that isn't a hero. 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.
Skywrath Mage
* Heroes with a low health pool (Crystal Maiden, Skywrath Mage etc)
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.
Skywrath Mage
* In the early-mid game, Skywrath consistently needs to use his entire mana pool to kill a hero, but Wraith King's 
Reincarnation allows him to finish off Skywrath after the first death, as Skywrath Mage will have likely expended all his mana.
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
* 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
Skywrath Mage
* 
Arcane Bolt can target Terrorblade's low health pool in the laning phase.
* Ancient Seal can prevent Terrorblade from casting Sunder.
* 
Mystic Flare can be used to great effect to burst Terrorblade down before he gets a Manta Style or a Black King Bar.
Keeper of the Light
* Heroes with summons/illusions/neutral creep armies: Beastmaster, 
Chen, Naga Siren
Skywrath Mage
* Heroes with either magical, physical or pure damage burst: 
Bane, 
Ember Spirit, 
Leshrac, Lina, 
Luna, 
Nyx Assassin, Phantom Assassin, Skywrath Mage, Tinker, 
Ursa, 
Void Spirit.
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.
Skywrath Mage
* Heroes that can easily kill Faceless Void from outside his Cronosphere; 
Sniper, Skywrath Mage, etc.
Skywrath Mage
* Magical burst damage is Timbersaw's weakness, and Ancient Seal not only amplifies it but also prevents him from using 
Timber Chain to escape for up to 6 seconds.
* He generally doesn't build early items to deal with silences.
* 
Reactive Armor does not trigger on magic damage or spells, meaning that even a 
Pipe of Insight won't give him the massive sustain he normally gets from attacks.
Additional:
* Skywrath Mage's long range and low cooldown magic damage spells can easily harass Timbersaw out of lane.
* Ancient Seal is not only a long lasting silence, (one of Timbersaw's biggest weaknesses) but it also makes him even more vulnerable to magical burst damage.
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
Skywrath Mage
* 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.
Skywrath Mage
* Ancient Seal instantly shuts down Dark Willow's abilities, rendering her defenseless against his high burst damage spells, while she cannot cast spells of her own.
* Mystic Flare deals immense burst damage in an area, damaging Dark Willow through Shadow Realm.
Skywrath Mage
* Skywrath Mage can easily harass Alchemist in the laning phase with multiple Arcane Bolts. Additionally, if Alchemist is in the process of throwing an 
Unstable Concoction, and has no way to dispel Ancient Seal, the self stun becomes an easy set up for Mystic Flare.
* Caution, however, as a decently farmed Alchemist with {Item ID:Radiance} and {Item ID:Manta Style} can easily send illusions to harass and force Skywrath Mage out.
Skywrath Mage
* Arcane Bolt allows Skywrath Mage to harass Earthshaker out of lane.
* Ancient Seal is an instant silence that can be pre-cast onto Earthshaker to disrupt his combo, before he uses 
Blink Dagger to initiate.
* Mystic Flare will nuke Earthshaker down while he stands in place during his long cast animations.
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.
Skywrath Mage
* Arcane Bolt's low cooldown allows him to deal consistent damage to Morphling, and is a viable way to disable Linken's Sphere.
* Ancient Seal prevents Morphling from using any of his skills, giving Skywrath Mage and his team ample time to burst Morphling down.
* Mystic Flare coupled with a stun/root can easily burst Morphling down, especially if he has more stats shifted to Agility.
* Alternatively, Morphling can use Morph to use Skywrath Mage's own silence and nukes against him.
Skywrath Mage
* Skywrath Mage stands perfectly on the center line against Tinker, thanks to his nuke and silence. Also, thanks to his abilities, he can quickly kill a victim, and Tinker is one of the most subtle heroes in the game
Additional:
* Skywrath Mage stands perfectly on the center line against Tinker, thanks to his nuke and silence. Also, thanks to his abilities, he can quickly kill a victim, and Tinker is one of the most subtle heroes in the game
Skywrath Mage
* Skywrath Mage should have the upper hand against Vengeful Spirit with Ancient Seal.
* Vengeful is highly dependant on her abilities and has no natural means to deal against silences.
* Her low attack range allows Skywrath Mage to easily bully her out of the lane.
Skywrath Mage
* 
Cold Embrace is a perfect setup for Mystic Flare.
* Winter Wyvern is a spellcaster, and the 6 second silence from Ancient Seal can prevent her from contributing much.
* Because Skywrath Mage tends to stay back in fights, Winter Wyvern will have to get close to a teamfight to cast 
Winter's Curse on him. And if she chooses to cast it on one of his allies, his low attack speed and damage means that he won't do much.
* However, bear in mind that Skywrath Mage has seriously awful armor, and that can make him an adequate target to being turned against his own team with Winter's Curse, which can result in his death quickly.
Additional:
* Cold Embrace is the perfect setup for Mystic Flare, and his 6-second silence is good against Winter Wyvern in general.
Skywrath Mage
* Heroes with nukes: Bane, Lich, Lion, Skywrath Mage
Additional:
* 
Untouchable is useless versus constant Arcane Bolts, and it doesn't help that her strength gain is the lowest in the game.
* A jungle Enchantress can weaken lanes and make Skywrath Mage's job easier.
* The magic amplification from Ancient Seal makes her even squishier to Skywrath and his allies' magic nukes.
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
Skywrath Mage
* 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.
Skywrath Mage
* Heroes with high magical or pure damage will bypass Bulwark: 
Timbersaw, 
Dark Willow, Enigma, 
Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.
Keeper of the Light
* Melee carries during the laning phase: 
Sven, Slark
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.
Skywrath Mage
* Heroes with powerful spammable abilities will prove problematic for Grimstroke as Ink Swell does not protect him from them: Zeus, Skywrath Mage, Tinker, Lina
Skywrath Mage
* Even though 
Linken's Sphere will block your silence, you can cast Arcane Bolt to break it or wait until someone on your team breaks it. In addition, Linken's Sphere builders are usually squishy targets vulnerable to silences: 
Weaver, 
Queen of Pain, 
Morphling, Clinkz, etc. Don't forget that Ancient Seal also increases the magical damage these enemies take, along with silencing them.
Additional:
* Arcane Bolt has a long range and a low cooldown, and is a great spell to waste Linken's Sphere. It also serves as an effective spell to harass Weaver with.
* Ancient Seal prevents Weaver from using Shukuchi or Time Lapse.
Skywrath Mage
* Lich is heavily reliant on his abilities to contribute to team fights, so be wary of enemies that can Silence: 
Bloodseeker, 
Death Prophet, Silencer, 
Drow Ranger, Skywrath Mage.
Skywrath Mage
* Heroes with long range abilities are also able to touch Zeus, such as 
Clockwerk, Kunkka, Puck, Skywrath Mage, 
Spirit Breaker, 
Tusk and others.
Keeper of the Light
* Heroes that punish mobile heroes: Bloodseeker, Keeper of the Light, Kunkka, 
Disruptor.
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
* 
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
Skywrath Mage
* Mystic Flare can easily burst down Legion Commander while she is Dueling.
Skywrath Mage
* Silence (and mana burns) will be a persistent problem for Phoenix, as it is heavily reliant on its abilities whether defensively or offensively, so heroes like Death Prophet, Skywrath Mage, and even Nyx Assassin must be closely observed to prevent being shut down by these heroes.
* Hexes are a greater threat to Phoenix as they also disable items, preventing Phoenix from dispelling the debuff on its own.
Skywrath Mage
* Skywrath Mage's Mystic Flare can deal huge damage to Clockwerk inside his Power Cogs.
Skywrath Mage
* Heroes with either magical, physical or pure damage burst: Bane, Ember Spirit, Leshrac, Lina, Luna, Nyx Assassin, Phantom Assassin, Skywrath Mage, Tinker, Ursa, Void Spirit.
Skywrath Mage
* Heroes with silence and mana drain abilites, as Ancient Apparition relies entirely on his abilities: Invoker, Silencer, Nyx Assassin, Skywrath Mage, Shadow Shaman, Lion and etc.
Keeper of the Light
* Heroes with teleports to escape Solar Blind and Will-O-Wisp: Phantom Assassin, Puck, Queen of Pain, 
Storm Spirit
Skywrath Mage
* Skywrath's pitiful defences also make him easy meat to heroes with high burst like Juggernaut, Lion, or Phantom Assassin, the latter occasionally downing a support Skywrath in a single Stifling Dagger.
Keeper of the Light
* Heroes which rely exclusively on right clicks will struggle somewhat against Blinding Light: Phantom Assassin, Wraith King, Medusa
Skywrath Mage
* While Phantom Assassin can kill Skywrath Mage in a few strikes, Skywrath Mage can also do the same to her if she is not careful.
* Arcane Bolt's long range and low cooldowns allows Skywrath Mage to severely harass Phantom Assassin in lane.
* Ancient Seal prevents Phantom Assassin from escaping or engaging with 
Phantom Strike.
* Mystic Flare's heavy magical damage nukes Phantom Assassin down quickly during the early to mid game.
Additional:
* While Phantom Assassin can kill Skywrath Mage in a few strikes, Skywrath Mage can also do the same to her if she is not careful.
* Arcane Bolt's long range and low cooldowns allows Skywrath Mage to severely harass Phantom Assassin in lane.
* Ancient Seal prevents Phantom Assassin from escaping or engaging with Phantom Strike.
* Mystic Flare's heavy magical damage nukes Phantom Assassin down quickly during the early to mid game.
Skywrath Mage
* Skywrath Mage also has a terrible time fighting against anything that isn't a hero. 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.
Keeper of the Light
* Illuminate clears Beastmaster's summons and is effective against his push.
Keeper of the Light
* Heroes with teleports to escape Solar Blind and Will-O-Wisp: Phantom Assassin, Puck, Queen of Pain, Storm Spirit
Skywrath Mage
* Similar to Timbersaw, Storm Spirit builds items that don't help against silences.
* An 
Orchid Malevolence will most likely silence you first. However, if you grab a 
Eul's Scepter of Divinity, you might dispel his silence and turn the tides to your favor.
* Root and silence are Storm Spirit's ultimate counters. Skywrath Mage has a silence in his kit, and has 
Rod of Atos as his core item. If he dispels one, you cast the other, both leaving him vulnerable.
* If he builds Black King Bar, he spends 4050 gold that doesn't help him snowball effectively.
Keeper of the Light
* Heroes with teleports to escape Solar Blind and Will-O-Wisp: Phantom Assassin, Puck, Queen of Pain, Storm Spirit
Skywrath Mage
* A good Skywrath Mage with quick fingers will punish Queen of Pain for blinking aggressively. Ancient Seal is a six second silence with no cast time, so he can interrupt either her Shadow Strike or Sonic Wave, and a good Mystic Flare on top of that will seal the deal for her.
* Ancient Seal also has pretty good range so he could get it off before she blinks away.
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.
Skywrath Mage
* Ancient Seal can silence Jakiro and make him vulnerable to magical spells up to 6 seconds.
* Skywrath Mage can usually burst down Jakiro with his high damage magical spells.
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.
Skywrath Mage
* Skywrath Mage also has a terrible time fighting against anything that isn't a hero. 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.
Skywrath Mage
* Mystic Flare can be used to effectively ignore the Spirit Bear entirely and burst Lone Druid during the early mid game.
* 
Concussive Shot and Arcane Bolt will provide vision of Lone Druid allowing for better chase in teamfights before the Spirit Bear can do too much damage.
* Ancient Seal denies the ability to transform into 
True Form and receive bonus HP from the skill.
Skywrath Mage
* Skywrath Mage's very low health allows Monkey King to ambush and finish him off quickly.
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.
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 silences: Puck, Doom, Riki.
Keeper of the Light
* Heroes who are strong against mobile heroes: Disruptor, Bloodseeker, Kunkka, Keeper of the Light.
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.
Skywrath Mage
* Even though Linken's Sphere will block your silence, you can cast Arcane Bolt to break it or wait until someone on your team breaks it. In addition, Linken's Sphere builders are usually squishy targets vulnerable to silences: Weaver, Queen of Pain, Morphling, Clinkz, etc. Don't forget that Ancient Seal also increases the magical damage these enemies take, along with silencing them.
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
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
Skywrath Mage
* Due to the high mana cost of his spells and the low cool down of them, Nether Ward can seriously damage Skywrath Mage if he isn't careful.
Nether Ward will make Skywrath Mage next to useless in fights, as his low hp pool will not allow him to sustain through the damage of the ward should he choose to cast spells. Be wary though that Skywrath's huge burst will make very quick work of Pugna's low hp should the ward be destroyed, and 
Decrepify won't help Pugna at all.
* Skywrath Mage's fragility makes him very susceptible to Pugna's high burst damage.
Additional:
*