* Arcane Curse stacks every time Bristleback uses an ability, forcing him to stop spamming his abilities, or take heavy health degeneration.
* Glaives of Wisdom steals intelligence both permanently and temporarily, causing mana issues for Bristleback.
* Last Word and Global Silence stops Bristleback from using his abilities altogether.
Additional:
* Bristleback will not be able to cast Viscous Nasal Goo or Quill Spray while silenced, effectively blocking a major part of the hero's damage and preventing Warpath charges from stacking.
* Arcane Curse slows Bristleback down and lasts longer the more abilities he uses. On the other hand, if he doesn't use any abilities, he will begin to lose Warpath charges.

* Essence Shift allows Slark to hit bristleback freely whether on the front or back, stealing attributes and make bristleback much less tanky.
* Pounce can be used to disengage and recover loss HP with his ultimate passive, and can return to fight in a short period while bristleback is already injured and got some of his attributes stolen.
* Dark Pact makes it near impossible to keep Viscous Nasal Goo debuff on slark.
* Although Dark Pact cannot dispel Quill Spray, means Slark will still receive quill stack damage even if he uses Shadow Dance before.
* Slark builds Silver Edge in almost every game, an item that greatly counter birstleback.

* Silencer burns easily through her effective HP from Mana Shield, by taking away her intelligence.
* Arcane Curse punishes her repeatedly casting Mystic Snake to keep her mana pool high. He can force her to use Manta Style before he has cast Global Silence and Medusa usually does not want to build Black King Bar.

* Medusa is especially vulnerable to Essence Shift, as both strength and intelligence contribute to her effective HP, while agility contributes to her damage.
* Dark Pact when timed right can be used to dispel Stone Gaze right after it petrifies Slark, allowing him to keep attacking Medusa throughout the duration.
Additional:
* Medusa cannot chase Slark in any way and has no disable beyond her ultimate, making her unable to stop him getting away and regenerating before coming back to finish her off.
* Essence Shift particularly removes 1 intelligence point per hit, thus lowering Medusa's mana pool's cap and leaving her much more vulnerable in prolonged fights.

* Because Warlock's abilities are all active abilities, Silencer can make his impact minimal.
* Arcane Curse prevents Warlock from using his abilities without increasing it's duration, which since all of Warlock's abilities are actives it is very effective against him.
* Last Word can prevent Warlock from casting his Fatal Bonds, Chaotic Offering, and Upheaval combo.
* Global Silence can nullify Warlock's impact in fights by preventing him from casting Fatal Bonds and Chaotic Offering, or by interrupting his Upheaval.

* Upheaval does not interrupt Slark too much, as he can just Pounce out of the area.
* Fatal Bonds and Shadow Word can be dispelled by Dark Pact.

* Silencer can stop Rearm, preventing Tinker from spamming his abilities/items or escaping.
* Tinker heavily relies on his mana pool and has mana issues throughout the entire game and Silencer's intelligence steal does not help with that.
Additional:
* As Tinker relies heavily on his spells to be effective, Last Word and Global Silence will render him largely useless.
* Arcane Curse effectively prevents Tinker from casting spells during its duration, as he will otherwise suffer heavy damage.
* Glaives of Wisdom deal pure damage, which make quick work of fragile heroes like Tinker.
* Silencer's intelligence steal permanently weakens Tinker since he's a hero who requires lots of mana to be effective.

* Pounce prevents Tinker from blinking away.
* Slark frequently builds Shadow Blade, which allows him to approach Tinker unnoticed. Since Tinker's farming usually covers a significant amount of area on the map, Sentry Wards may not be cost effective.
* Shadow Dance allows Slark to detect both common and unusual wards. Eliminating common ward causes Tinker trouble farming many lanes if he does not know who may be waiting to jump on him. Slark is also uniquely able to identify some of the less common wards used by Tinker, such as those placed on the cliffs at map edges which Tinker uses to give him vision over the trees he uses to hide in.
* Slark's extremely high move speed from Shadow Dance, potentially stacked with Shadow Blade, allows him to easily follow Tinker between lanes, especially if Tinker has pushed the lanes out.
* Dark Pact dispels Laser's blind.

* Heroes with low mana pools (eg.Doom andTidehunter) will feel the effects of Silencer's Intelligence Steal far more than others.

* Dark Pact dispels debuffs from Gush, Anchor Smash and even Ravage if timed correctly.
* Kraken Shell cannot restore attributes stolen by Essence Shift or dispel the leash if he gets Pounced.

* Arcane Curse can be cast from a long range to put Enigma's Blink Dagger on cooldown.
* Global Silence can interrupt Enigma's Black Hole channeling through Black King Bar and Linken's Sphere, making Silencer one of Enigma's hard counters. But bear in mind that Global Silence can be dispelled with Black King Bar if activated first.
Additional:
* Silencer can easily ruin Enigma's initiation, as Global Silence cancels Black Hole, even through Black King Bar and Linken's Sphere.

* Enigma lacks burst damage, and that makes him vulnerable to heroes who can recover themselves and turn the fight around to their advantage after Enigma finishes his initiation: Faceless Void, Terrorblade, Ursa, Weaver, Broodmother, Slark, Abaddon, Wraith King, Lifestealer.

* Silencer will most likely disrupt an initiation with his ultimate, Global Silence, prevent escape with his Last Word, and if Phoenix happens to die to him (or near him) enough times, he would sap enough of Phoenix's much needed Intelligence to make him a stronger foe and Phoenix with less mana than it already had.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* Heroes with silences and hard stuns such as Doom, Silencer, and Lion can keep Mirana from Leaping away.

* If Slark sees the Sacred Arrow before it hits him, he can use Dark Pact to remove it a moment later.
* Pounce prevents Mirana from escaping with Leap.
* Slark can survive Mirana's Aghanim's Scepter​ combo with Shadow Dance.

* Arcane Curse discourages Lina from using her abilities, preventing her from building up Fiery Soul stacks.
* Last Word and Global Silence are great against Lina for the same reason, as well as interrupting her combos and preventing her from casting spells.

* Dark Pact can be cast during the cast animation of Light Strike Array and dispel its stun.
* Pounce allows Slark to close the gap to Lina.
* Shadow Dance prevents Lina from killing Slark with her Laguna Blade when his HP gets low.

* Heroes with silencing abilities that are not blocked by Linken's Sphere, like Puck's Waning Rift, Death Prophet's Silence or Silencer's Global Silence.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* With 4 active abilities, Shadow Shaman is weak against silencing foes such as Silencer, Drow Ranger and Death Prophet.

* Nyx Assassin, Bounty Hunter and Slark can all sneak up and kill Shadow Shaman, Nyx being particularly deadly. Shadow Shaman must watch out for Slark carefully, as he can break either (but not both unless he makes a mistake) of Shadow Shaman's disables, with Dark Pact and leap out of a serpent ward ring. These heroes, however, rely heavily on escape and are themselves not very durable and none of them can survive a full lockdown with Mass Serpent Ward. Having Sentry Wards can turn Shadow Shaman from prey to predator.

* Terrorblade is a double-edged sword type of matchup against Silencer. Although Terrorblade is more reliant on direct attacks to be effective, he relies on Sunder to save himself and stay alive and Last Word and Global Silence prevent him from doing that.
* Arcane Curse and Aghanim's Scepter upgraded Last Word help Silencer deal with Terrorblade's illusions from Conjure Image and Manta Style.
* With Last Word Mutes talent, Silencer can not only disable Terrorblade from turning tables with Sunder, but can also prevent him from using Manta Style and Black King Bar, items Terrorblade needs to be effective in teamfights.
* Glaives of Wisdom deals pure damage against the real Terrorblade, bypassing his high base armor.
* Global Silence can silence Terrorblade even if he has Black King Bar active, though bear in mind that Terrorblade can dispel Global Silence with Manta Style and Black King Bar if the Global Silence was activated first.
Additional:
* Silencer is a double-edged sword type of matchup against Terrorblade. Although Terrorblade is more reliant on direct attacks to be effective, he relies on Sunder to save himself and stay alive and Last Word and Global Silence prevent him from doing that.
* Arcane Curse, Glaives of Wisdom upgraded with 2 Glaives of Wisdom Bounces talent and Aghanim's Scepter upgraded Last Word help Silencer deal with Terrorblade's illusions from Conjure Image and Manta Style.
* With Last Word Mutes talent, Silencer can not only disable Terrorblade from turning tables with Sunder, but can also prevent him from using Manta Style and Black King Bar, items Terrorblade needs to be effective in teamfights.
* Glaives of Wisdom deals pure damage against the real Terrorblade, bypassing his high base armor. Later it can be upgraded with 2 Glaives of Wisdom Bounces talent to deal against Terrorblade's illusions.
* Global Silence can silence Terrorblade even if he has Black King Bar active, though bear in mind that Terrorblade can dispel Global Silence with Manta Style and Black King Bar if the Global Silence was activated first.

* Lion is extremely dependent on his abilities. Silences like Silencer's Last Word, magic resistance like Oracle's Fate's Edict, and dispels like Legion Commander's Press the Attack all make his abilities less effective.

* Pounce allows Slark to close in on Lion and prevent him from escaping.
* Lion's fragile health pool makes him easy prey for Slark's high burst damage through Pounce, Dark Pact and right-clicks.
* Shadow Dance prevents Lion from casting Hex, Mana Drain, or Finger of Death on Slark.
* Dark Pact allows Slark to dispel any of Lion's disables.

* Timbersaw is heavily reliant on his abilities for damage and escape, allowing Silencer to effectively disable him and make him useless in both team fights and 1v1 scenarios.
Additional:
* Arcane Curse deals repeated stacks of damage to Timbersaw because he relies on constantly using his abilities.
* Glaives of Wisdom deals pure damage and when cast manually, nearby creeps will not attack silencer, making it an effective harassment tool.
* Although Last Word takes a while to trigger, it will break Timbersaw's ability combo and can be used to silence him.
* Global Silence will silence Timberaw no matter where he is on the map. This can be used to help allies get a kill on him, or prevent Timbersaw from killing someone.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* Shadow Demon's main source of damage is his low cooldown, high damage spells - meaning Last Word and Global Silence will pretty much take him out of the game for the duration.
* Shadow Demon likes to spam his abilities, which makes him vulnerable to Arcane Curse.
* If Shadow Demon dies near Silencer, he will lose intelligence, reducing his mana pool, mana regen, and attack damage. Furthermore, if the game is long and Shadow Demon dies often, the intelligence losses will also reduce his spell damage.

* Heroes who can dispel will be able to remove remove Soul Catcher's debuff to instantly bring the health of affected heroes back to a considerable amount: Abaddon, Slark, Legion Commander, Oracle.

* Kunkka relies on his powerful AOE spells to turn the tides of teamfights. He cannot use them while silenced.
* Last Word can mess up Kunkka's ability synergy, silencing him in the middle of his strong combo.
* Global Silence can disable Kunkka's spell casting from anywhere on the map, even if Kunkka is spell immune at the time.

* Shadow Dance allows Slark to not be targeted by Unstable Concoction, making Alchemist stun himself and making himself vulnerable to the enemy.
* Dark Pact also allows him to just purge off the stun if timed correctly.
* Essence Shift will steal stats over long durations at a time should Alchemist lack the damage to kill Slark.

* Slark's Pounce can be used to dodge Hoodwink's abilities or lock her down.
* Shadow Dance makes Slark unhittable from Acorn Shot.
* Dark Pact removes all slows from Hoodwink's abilities.
* Hoodwink's already low health output is a great target for Slark's Essence Shift.

* Dark Pact easily purges away both slow and disarm effect from Lucky Shot.
* With Pounce now applying leash to the target, Pangolier is helpless against Slark since both his Swashbuckle and Rolling Thunder will be disabled. Pounce also help Slark to easily escape from Rolling Thunder.

* Like any hero with a channeled spell, Last Word is a counter to it.
* Global Silence goes through spell immunity and prevents Witch Doctor from casting his spells.

* Dark Pact can dispel Flaming Lasso if is used in anticipation, but a Blink initiation from fog can catch the Slark off guard.
* Slark can also take off any Sticky Napalm stacks with Dark Pact in lane.
Additional:
* Shadow Dance's passive can inform Slark when he's under enemy vision, meaning it'll be very hard to catch Slark off-guard with Flaming Lasso.
* Flaming Lasso is dispelled by Dark Pact. Its casting can be prevented with Shadow Dance or Depth Shroud (it requires Aghanim's Shard).

* Invoker is heavily dependent on his spells, making him useless during Global Silence, as well as interrupting Invoker during his combo.
* Arcane Curse is particularly deadly, because Invoker will continuously lose health if he keeps invoking and casting new spells.
* Last Word will silence Invoker when he casts Invoke, interrupting his combo.

* Dark Pact dispels Ignite's slow and Fireblast's stun.
* Shadow Dance allows Slark to regenerate HP, even when he is affected by Ignite and Fireblast.

* Arctic Burn and Splinter Blast debuffs are dispellable with Dark Pact. Arctic Burn is also no escape against Pounce.
* Cold Embrace gives Slark free Essence Shift stacks.
* However, Essence Shift works against allies, and Slark's low health pool means that if he's the target for Winter's Curse, he will go down very quickly.

* Global Silence and Last Word can prevent Ember Spirit from casting Activate Fire Remnant to escape.
* Glaives of Wisdom also provide high pure damage that is not negated by Flame Guard.
* Arcane Curse is also a potent harassing tool in the laneing stage as its cooldown is lower than Flame Guard's.

* Global Silence stops Snapfire's Mortimer Kisses.
* Last Word can prevent Snapfire from casting additional spells.

* Silencer's abilities hamper Windranger's effectiveness in battle, preventing her from comboing abilities and escaping using Windrun.

* 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.

* Heroes with dispels: Legion Commander, Oracle, Slark, Phantom Lancer

* Basically, Heroes that heavily rely on abilities for damage or escape, such as Queen of Pain and Storm Spirit.

Additional:
* Silencer's Intelligence Steal can reduce Storm Spirit's damage output if he gets some kills on laning phase.
* Last Word and Global Silence will make Storm Spirit an easy target.
* Global Silence can be used to prevent Storm Spirit from connecting abilities after a Ball Lightning on his targets.

* Pounce's leash prevents Storm Spirit from using Ball Lightning, making it hard for Storm Spirit to escape a gank from Slark.
* Dark Pact can dispel Orchid Malevolence's Soul Burn.

* Dark Pact dispels Dismember if timed correctly.
* Pounce allows Slark to escape Pudge's Rot once Dismember is over, and allows him to dodge hooks.
* Shadow Dance hides Slark and grants him a high degree of mobility, which can make him a difficult target to hook and also protects him from Pudge's Dismember (including allies with an Aghanim's Shard).

* Zeus' main source of damage is his low cooldown, high damage spells - meaning Last Word and Global Silence will pretty much take him out of the game for the duration.
* Zeus likes to spam his abilities, which makes him vulnerable to Arcane Curse.
* If Zeus dies near Silencer, he will begin to lose intelligence, reducing his mana pool, mana regen, and attack damage. Furthermore, if the game is long and Zeus dies often, the intelligence losses will also reduce his spell damage.
Additional:
* Silencer's Global Silence will render Zeus useless for 6 seconds in a team fight.
* Arcane Curse will punish Zeus for casting spells, which can cause continuous damage to him should he continue to cast spells.
* Last Word can silence Zeus and prevent him from spamming his spells.
* Silencer often builds Orchid Malevolence (or Bloodthorn) which can be used on spell casters like Zeus, forcing him to invest in a Linken's Sphere.

* Zeus can deal a huge amount of damage, but he lacks defensive abilities, such as good mobility or resistance. Due to that, he doesn't like to be touched by any means. Heroes with higher damage output and good mobility will often get easily near Zeus and trade damage (eventually causing Zeus's downfall). Such Heroes include: Lycan, Slark, Storm Spirit, Spectre and others.

* Pounce's root prevents Earth Spirit from using Rolling Boulder to escape, making it easier for Slark to shut him down especially in the laning phase.

* Arcane Curse punishes Necrophos if tries to spam Death Pulse, increasing the duration of the slow and damage taken over time.
* Last Word heavily damages Necrophos and also silence him for a lenghty duration.
* Glaives of Wisdom will reduce temporarily Necrophos intelligence on each hit dealing hindering his ability to spam Death Pulse, also reducing his attack damage and mana pool; dealing increasing amounts of phisical and pure damage each time. Silencer will permanently steal Necrophos intelligence if Necrophos is killed by him or if he dies nears him.
* Global Silence turns Necrophos almost useless for a long time, allowing Silencer and his team to easily dispatch him, since Necrohpos heavily relies on his spells to survive.

* Dark Pact can dispel Venomous Gale and Poison Sting.
* Shadow Dance allows Slark heightened regeneration when out of vision making DoTs effects less threatening.

* Last Word and Arcane Curse have the range to hit Dark Willow beyond Bramble Maze.
* Global Silence renders Dark Willow useless in teamfights.

* Essence Shift deals 20 extra damage by draining one strength per hit, which cannot be reduced or spread by Dispersion.
* Pounce prevents Spectre from escaping with Spectral Dagger.
* Haunt illusions usually don't deal a lot of damage to Slark as he tends to buy a Shadow Blade, preventing Desolate's and Diffusal Blade's damage and activating Shadow Dance's regeneration to make up for any damage caused by Radiance.
* Slark is a natural carrier of Silver Edge, which helps break both Desolate and Dispersion.

* Pounce can easily break Static Link, making it less powerful against him.
* Slark is one of the few heroes who can man fight a Razor, because of Essence Shift.
* Shadow Dance can prevent Razor from killing him and may provide an opportunity to kill Razor due to it preventing Razor from attacking Slark.

* Arcane Curse can effectively discourage Undying from casting his spammable abilities in a team fight, as Undying will have to suffer more damage and the slow due to the penalty duration of Arcane Curse.
* Last Word and Global Silence are able to silence Undying for up to 6 seconds, preventing Undying from gaining strength and healing his ally or himself.

* 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.

* Pounce prevents Anti-Mage from using Blink, and lets him disengage from Anti-Mage if needed.
* Essence Shift allows Slark to permanently steal agility from Anti-Mage.
* Shadow Dance stops Anti-Mage from being able to fight back in a slippery situation.

* Heroes that can jump on her: Slark, Queen of Pain, Anti-Mage

* Pounce also stops Nature's Prophet's Teleportation.

* Global Silence has faster-cast animation than Chronosphere, making Silencer can silence Faceless Void before he can cast Chronosphere.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* Generally strong against every spellcaster, Puck fully relies on their skill set and is barely a threat when silenced.
* Arcane Curse disables Blink Dagger for quite some time, and is also effective against Puck as it tend to use its spells a lot.
* Glaives of Wisdom can do a lot of damage against Puck due to Puck's low agility gain and armor.
* Last Word can prevent Puck from getting a full combo off, limiting its effectiveness in team fights or ganks.
* Global Silence can take Puck out of fights entirely.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* 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.

* Heroes who have a high mobility (Queen of Pain, Storm Spirit, Slark, etc.).

* Both Arcane Curse and Last Word punishes casters with spammable spells such as Sand King.
* As a strength caster, Intelligence Steal reduces Sand King's mana pool even more.
* Global Silence silences Sand King, effectively reducing Sand King's initiation and counter-initiation potential. It can also interrupt channeling of Epicenter.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* Heroes with silence such as Riki, Silencer, or Night Stalker prevents Skywrath Mage from using his spells.

* Heroes with escaping and disjointing abilities can be good against Juggernaut:Anti-Mage Riki, Queen of Pain, Puck, Storm Spirit, Ember Spirit, Slark etc.

Additional:
* Blade Fury does not offer any protections against Essence Shift, as it can go through spell immunity and reduces attribute.
* Slark can pounce away from Juggernaut and he cannot prevent or chase slark.
* Shadow Dance prevent Juggernaut from using Omnislash altogether, while regen himself at a higher rate. Slark can freely hit juggernaut without any fears of retaliation.

* Silences and other types of lockdown that prevent Weaver from using his spells: Silencer, Riki, Lion, Legion Commander, Shadow Shaman, Bane.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* Heroes with strong dispels can remove Primal Roar's stun: Abaddon, Slark, Oracle.

* Silencer's Global Silence and Doom's Doom makes Earthshaker temporarily useless.

* Heroes with invisibility and high mobility can jump on and focus down Earthshaker before he has a chance to initiate: Clinkz, Slark, Storm Spirit

* Slark with Dark Pact
* 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.

* Heroes that can easily bypass Io's allies to get to Io: Riki, Tusk, Clinkz, Sniper, Slark, Phantom Assassin, Void Spirit, Storm Spirit, Ember Spirit, Earth Spirit, Spirit Breaker.

* Pounce and Dark Pact together with some attacks can take Rubick down quickly.
* Rubick's spells are ineffective due to the strong dispel effect of Dark Pact.
* Even though Shadow Dance is a great spell to steal, Slark's untargetable nature and his low cooldown spells prevents Rubick from stealing. Also Slark can freely use other abilities for the duration of Shadow Dance.

* Dark Pact rips through Refraction charges and still steals attributes during Refraction.
* Pounce and Dark Pact will still hit Templar Assassin while she is Melded. Since she cannot move, both abilities will be easy for Slark to land.

* Dark Pact, if timed correctly, can dispel Wraithfire Blast's stun and slow.
* Since Wraith King has a lot of health and multiple lives, Slark can keep gaining Essence Shift stacks, increasing armor, damage, and attack speed and can beat down Wraith King twice.
* Slark sometimes carries Diffusal Blade to burn mana as an attempt to shut down Reincarnation.
* Because Wraith King has no AoE abilities, Shadow Dance is particularly useful against Wraith King.

* Shadow Dance prevents Luna from damaging Slark, and together with Silver Edge he can easily chase her or escape from her.
* Luna has no way to escape from Pounce's leash.
* For the same reasons, Slark makes a very powerful ally for Luna when they are in the same team.
Additional:
* Luna's lack of mobility and escape abilities makes her easily to gank for Slark.
* Shadow Dance helps avoid all the damage from Eclipse.
* For the same reasons, Slark makes a very powerful ally for Luna when they are in the same team.

* Silencer's Last Word and Global Silence prevents Jakiro from casting any spell.
* A carry Silencer can easily take down a support Jakiro with his Glaives of Wisdom.

* A well-timed Dark Pact can dispel Frost Arrows and Gust, letting Slark engage and escape freely.
* Shadow Dance lets Slark quickly close the gap and deal heavy damage without giving Drow Ranger a chance to retaliate.
* Pounce counteracts Frost Arrows' slow, letting Slark easily pin Drow Ranger down or flee.
Additional:
* Pounce and items like Shadow Blade makes it very difficult for Drow Ranger to keep her distance from Slark, thereby losing her Marksmanship bonus.
* Gust is rarely enough to keep Slark at bay, as Drow Ranger has no movement abilities and will simply be chased down afterwards.
* Drow Ranger's heavy dependence on agility also makes her significantly weaker after being drained by Essence Shift.

* A well-timed Global Silence prevents Dazzle from saving allies with Shallow Grave or Shadow Wave. Items that could dispel the silence are expensive, and difficult for Dazzle to farm from a support role.
* Arcane Curse and Last Word cause long damage over time, which may outlast Shallow Grave.

* Basically, Heroes that heavily rely on abilities for damage or escape, such as Queen of Pain and Storm Spirit.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* Sniper hugely lacks mobility and escape abilities so that he is an easy target for ganks from Slark.

* Silencer can reduce her damage with his Glaives of Wisdom, and as the primary item for him is the Revenant's Brooch, he can kill her through Pierce the Veil
* Silencer has a reliable and high ranged silence in Last Word and Global Silence, preventing Muerta from using her spells as effectivly
* Muerta likes to use her spells, particularly Dead Shot, Arcane Curse punishes her for doing so

* Heroes with low mana pools (eg.Doom andTidehunter) will feel the effects of Silencer's Intelligence Steal far more than others.

* Pugna is very reliant on his abilities for damage which Silencer can take advantage off. But he has to be careful around the Nether Ward as Silencer's abilities cost a lot of mana to use.

* Shadow Dance allows Slark to attack Lifestealer for its duration without any way for Lifestealer to fight back, allowing him to steal his stats with Essence Shift, which also reduces Lifestealer's strength and, therefore, health pool.
* Slark can easily escape Lifestealer with Pounce, and can avoid Open Wounds with Dark Pact should Lifestealer be forced to itemize for it.
* Slark commonly buys a Silver Edge, which can break Lifestealer's Feast, severely diminishing his damage output and lifesteal.

* Crystal Maiden is squishy, is heavily spell reliant, has low base Intelligence, and is naturally slow, making her an ideal target for Silencer.
* Crystal Maiden's Freezing Field has a similar cooldown to Global Silence, therefore, Freezing Field can almost always be canceled to ruin aggressive Crystal Maiden initiations.

* 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.

* 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.

* Silencer's Intelligence Steal will heavily reduce Outworld Destroyer's damage output, particularly from Sanity's Eclipse.
* Last Word and Global Silence will take Outworld Destroyer out of the fight unless he has built Black King Bar.
Additional:
* Silencer's intelligence steal will heavily reduce Outworld Destroyer's damage output, especially if Destroyer dies a lot near Silencer and loses intelligence permanently.
* Global Silence and Last Word will render Outworld Destroyer helpless unless he has an item/ally to dispel silence.

* Oracle's reliance on spamming his spells can be easily hindered by Silencer's Arcane Curse.
* Last Word and Global Silence negates Oracle's attempt to save his allies with his spells.
* Fate's Edict is useless against Glaives of Wisdom's pure damage.

* Dark Seer relies on Surge for most of his mobility, so he's not very vulnerable to slows, but much more to root effects and walls or pseudo-walls such as Disruptor's Kinetic Field or Slark's Pounce.

* Slark can detect early Roshan attempts due to Shadow Dance if he frequently checks the Pit.
* Enrage cannot restore attributes stolen by Essence Shift and will reduce his physical damage output.
* Even if Ursa initiates with Earthshock, Slark can Pounce away or use Dark Pact after Ursa's initiation to avoid Fury Swipes' damage until Earthshock's slow is gone.

* Heroes with pure damage can kill Huskar when he inevitably gets low on health: Outworld Destroyer, Silencer.

* Melee carries who usually buy an early Black King Bar, and have gap closing abilities can be good against the Arc Warden, such as Slark, Riki, Earthshaker with Aghanim's Scepter, Sven with Aghanim's Scepter etc.

Additional:
* Flux is dispelled by Dark Pact.
* Pounce allows Slark to avoid Spark Wraiths.
* Tempest Double allows Slark to build up Essence Shift stacks, especially when it is being used for split pushing.

* Heroes with blink or movement abilities, which are disabled by Pounce's leash: Anti-Mage, Earth Spirit, Faceless Void, Magnus, Mirana, Monkey King, Morphling, Pangolier, Phantom Assassin, Phoenix, Puck, Queen of Pain, Riki, Sand King, Spirit Breaker, Timbersaw, Tusk.

* Global Silence takes Omniknight out of the fight completely.
* Glaives of Wisdom are a great harass vs Omniknight during the laning stages of the game, since it doesn't aggro creeps & ignores his high base armor. It deals pure damage, which means it can also go through Guardian Angel.
* Silencer's intelligence steal can also cause Omniknight to falter in the early phases as it reduces his ability to use his spells.