* Medusa's tankiness doesn't help her very much against Fury Swipes in long teamfights.
* With no escape mechanism and a slow movement speed, getting jumped on by Ursa usually spells a quick end for Medusa in the early game.
Additional:
* Ursa's status resistance from Enrage will ignore Medusa's gaze.
* Ursa can stack damage with Fury Swipes easily against her Mana Shield in a prolonged team match.

* 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 removes 1 of every attribute, lowering Medusa's mana pool's cap and leaving her much more vulnerable in prolonged fights.
Additional:
* 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.

* Dark Pact dispels Dismember if timed perfectly.
* Pudge's low attack speed and poor agility can be lowered even further by Essence Shift.
* Shadow Dance grants Slark invisibility and a high degree of mobility, which can make Slark a difficult target to hook and also protects him from Pudge's Dismember (including allies with an Aghanim's Scepter).

* Low armor and lack of escape makes Pudge vulnerable to Ursa, specially when he gets his Blink Dagger.
* If Pudge lands a Meat Hook on Ursa, Ursa can simply face Pudge head on provided he can burst him down before any follow up disables.
* Enrage's Aghanim's Scepter upgrade allows Ursa to dispel Pudge's Dismember.

* Dark Pact can be used to remove Open Wounds.
* Shadow Dance allows Slark to attack Lifestealer for its duration without any way for Lifestealer to fight back.
* Slark commonly buys a Silver Edge, which can break Lifestealer's Feast, severely diminishing his damage output and lifesteal.

* Lifestealer's Feast will most likely not out-heal the damage from Fury Swipes and Overpower in the early to mid game.
Additional:
* Lifestealer can't fight Ursa in any stage of the game because of his high physical damage with Fury Swipes and Overpower.

* 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.

* Enrage with Aghanim's Scepter can dispel Flaming Lasso.

* Fury Swipes will keep stacking on Tidehunter since it cannot be dispelled by Kraken Shell and its bonus damage cannot be reduced by Anchor Smash.
* Enrage dispels the slow from Gush, and if upgraded with Aghanim's Scepter, can even dispel Ravage's stun.

* 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.

* Chemical Rage will rarely save Alchemist against Ursa's Fury Swipes.
* Enrage allows Ursa to both be a threat to Alchemist and avoid his over time damage.

* 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.

* 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.

* Ursa can easily unleash a number of attacks in an incredibly short amount of time, easily destroying the Supernova in a couple of seconds regardless of Fire Spirits' debuff. His Enrage also dampens any damage Phoenix might toss at his direction, as well as remove any debuffs Phoenix may place on him.

* Ursa can shred {U:Warlock Golem}s in a few seconds with Fury Swipes and Overpower.

* 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.

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

* Fury Swipes is not protected by Blade Fury and allows Ursa to harass Juggernaut anytime.
* Enrage reduces the damage taken from Omnislash.

* 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.

* Light Strike Array has a long delay, making her vulnerable for Ursa's burst.
* Enrage can protect Ursa against Lina's high magical burst.

* Silencer relies on preventing enemies from using abilities in teamfights with Arcane Curse, Last Word, and Global Silence. However, they are ineffective against Ursa since he relies more on items and attacks than abilities.
* Enrage reduces all damage taken, even Glaives of Wisdom's pure damage.

* Slark's Dark Pact allows him to dispel Silencer's debuffs.
* Against a carry Silencer, Essence Shift will lower damage from both Glaives of Wisdom and his basic attack.

* Ursa's massive physical damage can destroy Kunkka quickly.
* Enrage can be activated before being hit by Ghostship to prevent most of the damage.
* Earthshock slows Kunkka's movement speed. With no escape abilities, Kunkka is easy prey.

* Bristleback's tankiness doesn't help him very much against Fury Swipes in long teamfights.
* With no escape mechanism and a slow movement speed, getting jumped on by Ursa usually spell a quick end for Bristleback in the early game.

* Pounce and Dark Pact together with some attacks can gank Rubick down quickly. Rubick can seldom retaliate because of the strong dispel of Dark Pact. What is more, Rubick is the type of squishy support that Slark exactly wants to gank.
* Though Shadow Dance is a great spell to steal, Slark's untargetable nature and his low cooldown spells prevents Rubick from stealing it.
* Slark usually builds Diffusal Blade which can prevent Rubick to cast his abilities from Spell Steal.

* Slark is a natural Shadow Blade carrier, and with Pounce Sniper has no opportunity to escape or react.
* With Essence Shift and Shadow Dance, Slark will easily win a fight against Sniper.
Additional:
* Sniper is one of the most gankable heroes in the game, and has no defenses when Pounced on by Slark.

* Ursa deals lots of damage during the laning phase before Terrorblade has Sunder available.
* Enrage's damage reduction helps Ursa survive after Terrorblade has used Sunder.

* Enrage will make it very difficult to burst him down.
* Zeus has little armor, HP and mobility; Ursa's favorite kind of target.

* 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.

* Fury swipes can tear Dragon knight down as it stacks infinitely.

* 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.

* 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.

* Dark Pact easily purges away both slow and disarm effect from Lucky Shot.
* With Pounce now apply 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.

* All assassin-type carries in a one against one situation: Meepo, Phantom Assassin, Riki, Ursa.

* Shadow Dance prevents Luna from damaging Slark, and together with Shadow Blade he can kite her or escape.
* Luna has no way to escape from Pounce's leash.
Additional:
* Luna's lack of mobility and escape abilities makes her easily gankable by Slark.
* Shadow Dance will avoid all the damage from Eclipse.
* For the same reasons, Slark is a good ally for Luna when they are in the same team.

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

* 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 just gives Slark free Essence Shift stacks. He also relies mostly on magic damage early in the game.

* Jumping on Ursa with Life Break is often suicide for Huskar, as he will be immediately bursted down with Fury Swipes.
Additional:
* Huskar likes fights with a long duration and is usually at low health, making him vulnerable against Ursa's physical damage.
* Jumping in with Life Break against Ursa is suicide, as Enrage, Overpower, and Fury Swipes will easily shred Huskar.

* 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.

* 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.

* 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.

* 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.

* 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.

* Legion Commander is unlikely to win a Duel against Ursa.

Additional:
* Enrage's instant cast time allows it to be used before Legion Commander initiates a Duel, causing Ursa to take almost no damage for a brief period of time.
* Fury Swipes can give Ursa the edge in Duels.

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

* Timbersaw's physical survivability revolves around Reactive Armor, which is largely ignored by Fury Swipes due to the potentially large damage.
* Timbersaw's magical burst damage will not do much against Enrage, although he could easily use Timber Chain to escape, wasting the duration of it.

* 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.

* 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.

* Enemies that possess high defenses through magic resistance, damage reduction, or high regeneration will make it difficult to whittle their health down to get to Reaper's Scythe's threshold. Such heroes include Bristleback (although only from behind), Spectre, Ursa, and Dragon Knight.

* Heroes with burst damage of their own won't be afraid to go toe to toe with Void Spirit, like Ursa, Lifestealer, or Axe.

* 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.

* Nyx Assassin, Bounty Hunter and Slark can all sneak up and kill you, Nyx being particularly deadly. Watch Slark carefully, as he can break either (but not both unless you are making a mistake) of your 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 you from prey to predator.

* Ursa with Enrage
* 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.

* 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.

* Enigma is fragile, and lacks escapes, being dependent on Blink Dagger for mobility. Ganking Heroes or Heroes with burst damage will likely kill him before he can do anything. Such Heroes include: Lina, Lion, Puck, Slark, Nyx Assassin, etc.

* Slark's Pounce allows him to close the gap on Phantom Assassin and prevent her from escaping with Phantom Strike.
* As a hero who always goes for the Silver Edge and Abyssal Blade Slark can use it to disable Phantom Assassin and her Blur and Coup de Grace, drastically reducing her damage output and ability to evade attacks, and also preventing her from acting.
* Phantom Assassin's Coup de Grace requires Random Number Generation in order to proc, which gives Slark more than enough time to escape and recover himself.

* 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.

* Ursa's high physical burst damage makes him a very bad target for Power Cogs.
* Even with Blade Mail, Ursa's Enrage will negate most of the reflected damage.

* Provided Ursa can stack Fury Swipes reliably, Atrophy Aura won't do much against it.
* With Overpower, Fury Swipes, and Enrage Ursa could kill Underlord before the latter escapes with Dark Rift.
Additional:
* Fury Swipes damage is not reduced by Atrophy Aura, essentially bypassing Underlord's only natural defense.
* Enrage can quickly dispel the root of Pit of Malice.

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

* Heroes with dispels: Legion Commander, Oracle, Slark

* Enrage reduces the damage from Blade Mail and Counter Helix to a minimum, forcing Axe to play around Ursa's ultimate ability.
* Enrage and Fury Swipes tear through Axe's low armor, even if he has relatively high health.

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

* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Pugna
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Pugna

Additional:
* 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 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.