Lycan
* 
Dragon Knight's insanely high armor and splash damage can cause Lycan to struggle taking him down.
Nyx Assassin
* Dragon Knight's heavy armor negates 
Vendetta's burst physical damage. His large HP pool also gives him a good chance of surviving Nyx Assassin's follow-up nuke damage.
Lycan
* Rupture completely negates Lycan's high mobility.
* All of Lycan's summons are good sources of healing with Bloodrage.
Additional:
* 
Rupture completely negates Lycan's high mobility.
* All of Lycan's summons are good sources of healing with 
Bloodrage.
Nyx Assassin
* Heroes with invisibility will be detected by Thirst when they have low enough health: 
Bounty Hunter, 
Templar Assassin, 
Riki, 
Clinkz, 
Weaver, 
Treant Protector, 
Nyx Assassin.
Additional:
* While Burrowing, Nyx is an easy target for a 
Blood Rite, and his only way to counter it is a well-timed 
Spiked Carapace.
* 
Thirst is always a threat to Nyx Assassin, hindering his attempt of escape using Vendetta and rendering him unable to surprise Bloodseeker's allies.
* Rupture also prevents Nyx Assassin from escaping with Vendetta, as it forces him to stay still.
Lycan
* Heroes who rely on summons will see them destroyed easily by Overwhelming Odds: 
Lycan, 
Arc Warden, 
Warlock, 
Chen
Nyx Assassin
* Duel's long duration prevents Nyx Assassin escaping from Vendetta. With Aghanim's Scepter, she can also bypass Spiked Carapace.
Lycan
* Paralyzing cask bounces between him and his wolves, keeping him stunned for long amounts of time.
Nyx Assassin
* Heroes who build 
Black King Bar as either core or situational item will be able to fight back against Nyx Assassin and freely attack him as Spiked Carapace cannot pierce spell immunity at all: 
Axe, 
Broodmother, 
Dawnbreaker, 
Enigma, 
Huskar, 
Jakiro, 
Legion Commander, 
Lina, 
Luna, Lycan, 
Slardar, 
Slark, 
Troll Warlord, 
Witch Doctor.
Lycan
* Melee heroes who rely on summons, illusions, or clones will trigger Counter Helix more often, thus taking more damage: 
Meepo, Lycan, 
Phantom Lancer
Additional:
* 
Berserker's Call can keep Lycan in place during his Shapeshift even through Black King Bar.
* 
Counter Helix is very effective against Lycan because of his summons.
* 
Culling Blade will prevent Lycan from running away with Shapeshift when he drops low.
Nyx Assassin
* A well-timed Berserker's Call can expose Nyx Assassin while he is invisible with Vendetta, and prevent him from using Spiked Carapace.
* Axe can use 
Battle Hunger's damage over time to minimialize effects of Spiked Carapace.
* Axe's high health also allows him to easily shrug off Nyx Assassin's burst damage and fend him off. Especially since Axe is a common 
Heart of Tarrasque wielder, which can completely eliminate any chance for Nyx Assassin to kill Axe alone.
* Culling Blade can often kill Nyx Assassin as he is very fragile and vulnerable to damage while Spiked Carapace is on cooldown.
Additional:
* A well-timed Berserker's Call can expose Nyx Assassin while he is invisible with Vendetta, and prevent him from using Spiked Carapace.
* Axe can use Battle Hunger's damage over time to minimialize effects of Spiked Carapace.
* Axe's high health also allows him to easily shrug off Nyx Assassin's burst damage and fend him off. Especially since Axe is a common Heart of Tarrasque wielder, which can completely eliminate any chance for Nyx Assassin to kill Axe alone.
* Culling Blade can often kill Nyx Assassin as he is very fragile and vulnerable to damage while Spiked Carapace is on cooldown.
Lycan
* Lycan is a hero focused entirely on single target physical damage and lacks disables or AoE damage. Due to this, he will have difficulties dealing with illusions or Naga Siren's Ensnare.
Nyx Assassin
* Nyx Assassin's skillset is mostly single-targeted, therefore he will have difficulties against heroes with illusions and summons: 
Naga Siren, Broodmother, Lycan, 
Visage, Phantom Lancer. And to make things worse, Nyx Asassin is not a common 
Battle Fury, 
Maelstrom, 
Mjollnir, 
Gleipnir or 
Radiance wielder to counter this problem.
Lycan
* Jakiro's area-of-effect abilities make him strong against heroes who rely on illusions and summons: 
Terrorblade, Naga Siren 
Chaos Knight, Phantom Lancer, Broodmother, 
Nature's Prophet, Lycan, 
Wraith King, Visage.
Nyx Assassin
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: Jakiro, 
Viper, 
Venomancer, Huskar, 
Ember Spirit, 
Dark Seer, 
Sand King, 
Doom, Dawnbreaker. However, this also means they are easily stunned.
Lycan
* 
Faceless Void can lock Lycan down with his 
Chronosphere pinning him down as long as his ultimate is up.
Nyx Assassin
* Heroes who rely on invisibility, such as Bounty Hunter, Clinkz, 
Mirana, Nyx Assassin and Riki, as they will be revealed if caught by Chronosphere.
Lycan
* Lycan cannot escape from a Pounce even if he uses 
Shapeshift, and has no disabling abilities to stop Slark.
Nyx Assassin
* Heroes who build Black King Bar as either core or situational item will be able to fight back against Nyx Assassin and freely attack him as Spiked Carapace cannot pierce spell immunity at all: Axe, Broodmother, Dawnbreaker, Enigma, Huskar, Jakiro, Legion Commander, Lina, Luna, Lycan, Slardar, Slark, Troll Warlord, Witch Doctor.
Nyx Assassin
* Even though Visage's Familiars from 
Summon Familiars are fragile and can be killed quickly with Nyx Assassin's high burst damage, they can deal many instances of damage quickly, minimizing the effectiveness of Spiked Carapace.
* 
Gravekeeper's Cloak and tanky item builds make Visage hard for Nyx to kill with his burst damage. 
Aghanim's Shard upgraded Gravekeeper's Cloak also allows Visage to use 
Stone Form to both recover himself and stun Nyx Assassin if he is close enough to Visage.
* Visage's long range on 
Soul Assumption and 
Grave Chill make him hard to escape from, and Soul Assumption's low cooldown outmatches Spiked Carapace.
Nyx Assassin
* 
Blade Fury makes Juggernaut immune to all Nyx's abilities, except Vendetta.
* 
Omnislash. and 
Swiftslash can burst Nyx down, ignoring Spiked Carapace. However, Vendetta can be used to escape, canceling Omnislash/Swiftslash.
Additional:
* Juggernaut's entire skillset greatly counters Nyx Assassin's Spiked Carapace, his most important ability.
* Blade Fury allows Juggernaut to freely attack Nyx Assassin, and deal heavy damage to Nyx Assassin. Nyx Assassin cannot counter Blade Fury with Spiked Carapace because Blade Fury gives Juggernaut spell immunity. And besides Vendetta, Nyx Assassin has no other way of dealing damage to Juggernaut while he is spell immune.
* 
Healing Ward allows Juggernaut to recover himself and his allies from Nyx Assassin's damage output.
* Omnislash and Swiftslash from 
Aghanim's Scepter can quickly finish off Nyx Assassin. And just like Blade Fury, Nyx Assassin cannot counter neither Omnislash and Swiftslash from Aghanim's Scepter with Spiked Carapace because both abilities render Juggernaut invulnerable. And if Nyx Assassin has no Vendetta available to use for escaping, both abilities will kill him very quickly before he can do anything.
* Overall, any attempt for Nyx Assassin to gank and kill Juggernaut will hurt Nyx Assassin more than Juggernaut.
Lycan
* 
Arctic Burn allows Winter Wyvern to escape Lycan, even when he uses his ultimate.
* 
Splinter Blast is very effective in dealing with Lycan's summons.
* 
Cold Embrace saves allies from Lycan's raw physical damage and can buy allies enough time to turn the tide of battle.
* 
Winter's Curse stops Lycan in his tracks and is very effective because of his summons.
Additional:
* All of Lycan's damage is physical which is totally negated by Cold Embrace.
* Lycan often moves around with large amount of creeps, wolves created by 
Summon Wolves and neutral creep dominated by 
Helm of the Dominator which can be easily cleared by Splinter Blast or used as a great source of damage by Winter's Curse. If you catch Lycan with creeps nearby and affected by Shapeshift using Winter's Curse on him will most certainly end up with his death.
Lycan
* Can cast 
Demonic Conversion on one of Lycan's Wolves, making this a numbers fight.
* 
Malefice will greatly reduce his ability to engage
* 
Midnight Pulse can steep an area making it harder for Lycan to engage in.
Nyx Assassin
* Heroes who build Black King Bar as either core or situational item will be able to fight back against Nyx Assassin and freely attack him as Spiked Carapace cannot pierce spell immunity at all: Axe, Broodmother, Dawnbreaker, Enigma, Huskar, Jakiro, Legion Commander, Lina, Luna, Lycan, Slardar, Slark, Troll Warlord, Witch Doctor.
Nyx Assassin
* 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, Luna, 
Puck, Slark, Nyx Assassin, etc.
Additional:
* Enigma's uncontrollable damage from Malefice and Midnight Pulse make him easy to stun with Spiked Carapace.
* 
Black Hole can be easily interrupted by Impale or Spiked Carapace.
Nyx Assassin
* Nyx Assassin wants to start ganking as soon as he gets his Vendetta. Keeping him Tracked prevents him from ganking, and thus from doing his job in the game.
* Nyx Assassin has a lot of armor and health regen, making the nuke damage from Shuriken Toss very good against him.
Additional:
* 
Track hinders Nyx Assassin's ganking and escaping attempts with Vendetta, making him an easy kill for gold as well.
* Bounty Hunter can also use Track on Nyx Assassin while he has Spiked Carapace active without getting stunned as Track deals no damage at all before using 
Shuriken Toss.
Lycan
* A well landed 
Fissure can potentially take Lycan out of the fight for several seconds, who heavily relies on precious seconds from Black king bar and Shapeshift to fight.
* 
Aftershock reduces the effectiveness of his summons and can prove quite irritating for Lycan.
* 
Echo Slam is very powerful with the sheer amount of Lycan's units and will cause him to think twice when pushing towers.
Nyx Assassin
* 
Corrosive Haze hinders Nyx Assassin's ganking attempts with Vendetta, as well as reducing his armor and make him very vulnerable due to his low health pool.
* 
Guardian Sprint allows Slardar to catch up with Nyx Asssassin and finish him off if he has vision over him.
Lycan
* 
Great Cleave will kill Lycan's summons very rapidly.
* 
Warcry will allow Sven and his allies to tank Lycan's damage, which is mainly physical.
* 
Storm Hammer will damage and stun Lycan's as well as his summons.
Nyx Assassin
* Centaur's low Intelligence makes 
Mind Flare do low damage.
* With some creative skill builds, Centaur's Hoof Stomp stun duration should always last longer than Spiked Carapace stun, so escaping unscathed is hard for Nyx.
* With Blink Dagger and detection, Centaur can devastate Nyx in the open.
* However, bear in mind that Nyx can also easily initiate on Centaur Warrunner as well if he uses Spiked Carapace in anticipation, and with Vendetta. The damage from Retaliate will be reflected back to Centaur Warrunner, stunning him with no chance to react after he's revealed himself, and should guarantee a successful 
Impale.
Lycan
* 
Primal Roar allows Beastmaster to keep Lycan in place after he used his Shapeshift.
Lycan
* Tidebringer's cleave will cripple any of his summons.
* Could potentially build Heaven's Halberd to cripple Lycan even more.
Additional:
* 
Tidebringer can be used to kill Lycan's summons.
* Can also build into 
Heaven's Halberd which will disable Lycan's auto attacks, crippling him even more.
Nyx Assassin
* Even though Nyx Assassin can easily kill Luna with his high burst damage, Luna can also do the same to him if he is not careful.
* 
Lucent Beam can deal a fair amount of damage to Nyx Assassin if he has no Spiked Carapace available to use. Although Luna should be patient using Lucent Beam on Nyx Assassin when he uses Spiked Carapace.
* As Luna commonly buys Black King Bar, she can use it to freely attack Nyx Assassin whenever he tries to defend himself with Spiked Carapace during teamfights. Luna can also buy 
Eye of Skadi and 
Manta Style to survive Nyx Assassin's burst damage and distract him.
* Though Vendetta can deal serious damage to Luna and avoid 
Eclipse, smart Luna will always buy 
Dust of Appearance to provide vision on Nyx Assassin to her and her team.
Additional:
* Even though Nyx Assassin can easily kill Luna with his high burst damage, Luna can also do the same to him if he is not careful.
* Lucent Beam can deal a fair amount of damage to Nyx Assassin if he has no Spiked Carapace available to use. Although Luna should be patient using Lucent Beam on Nyx Assassin when he uses Spiked Carapace.
* As Luna commonly buys Black King Bar, she can use it to freely attack Nyx Assassin whenever he tries to defend himself with Spiked Carapace during teamfights. Luna can also buy Eye of Skadi and Manta Style to survive Nyx Assassin's burst damage and distract him.
* Though Vendetta can deal serious damage to Luna and avoid Eclipse, smart Luna will always buy Dust of Appearance to provide vision on Nyx Assassin to her and her team.
Lycan
* Lycan's wolves deal little damage to Bristleback, and are easily killed by Quill Spray, even when they're invisible.
* Lycan's lack of burst damage makes it very hard for him to kill Bristleback, especially when his back is turned.
Additional:
* 
Quill Spray can be used to kill Lycan's summons.
* 
Bristleback allows him to stay alive against Lycan while dishing out counter attacks
* He can overpower Lycan with his 
Warpath instead.
Nyx Assassin
* A well-timed 
Doom prevents Nyx Assassin escaping with Vendetta and fighting back with Spiked Carapace.
* Doom's high health also allows him to easily shrug off Nyx Assassin's burst damage and fend him off.
Lycan
* All of Timbersaw's spells deal AoE damage, killing Lycan's summons very quickly.
* 
Reactive Armor will gain stacks quickly because of Lycan's summons.
Nyx Assassin
* With Aghanim's Scepter, Broodmother will gain access to 
Spinner's Snare, which will allow her to create invisible lines on her webs from 
Spin Web that will root, deal damage over time, and reveal enemy heroes if they unwittingly step on them. This allows Broodmother to keep her allies alerted on heroes who rely on invisibility-themed and movement-themed abilities and items to surprise enemy heroes and disrupt ganking attempts of enemy heroes: 
Phantom Assassin, Nyx Assassin, Mirana, Bounty Hunter, Templar Assassin, Riki, 
Spirit Breaker, 
Anti-Mage, 
Tusk, 
Ursa, Nature's Prophet, Enigma, 
Void Spirit, 
Magnus etc.
Nyx Assassin
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: Jakiro, Viper, Venomancer, Huskar, Ember Spirit, Dark Seer, Sand King, Doom, Dawnbreaker. However, this also means they are easily stunned.
Nyx Assassin
* Heroes who build mana boosting items but have low mana regeneration are especially vulnerable against Mana Break and Mana Void: 
Timbersaw, Slark, 
Shadow Fiend, Clinkz, 
Bristleback Nyx Assassin, Magnus
Lycan
* Heroes who rely heavily on melee attacks and lack early spell immunity are easily blocked and interrupted by Ink Swell: Lycan, Ursa, Troll Warlord.
Additional:
* 
Stroke of Fate deals more damage when it hits more targets which makes it very effective in dealing with Lycan and his units.
* 
Soulbind prevents Lycan from running away and makes him very easy to deal with.
Nyx Assassin
* Heroes who build Black King Bar as either core or situational item will be able to fight back against Nyx Assassin and freely attack him as Spiked Carapace cannot pierce spell immunity at all: Axe, Broodmother, Dawnbreaker, Enigma, Huskar, Jakiro, Legion Commander, Lina, Luna, Lycan, Slardar, Slark, Troll Warlord, Witch Doctor.
Lycan
* Heroes that can summon units will have their summons destroyed very quickly if badly micro-managed, like Chen, Lycan, and Phantom Lancer.
Nyx Assassin
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: Jakiro, Viper, Venomancer, Huskar, Ember Spirit, Dark Seer, Sand King, Doom, Dawnbreaker. However, this also means they are easily stunned.
Lycan
* Treant Protector grants protection against his attacks with 
Living Armor and his ultimate, 
Overgrowth is a massive AoE disarm and root that pierces spell immunity, causing trouble to Lycan. You will find yourself in need of an ally's dispel or forced to pop Black King Bar for its dispel.
Additional:
* Lycan has no kind of teleport, being only able to walk, and heavily relies on his attacks. As Overgrowth roots and disarms the targets, Lycan can't do much in an overgrowth field.
Lycan
* Heroes who have summons, which can be quickly cleared by his powerful area of effect skill: Nature's Prophet, Enigma, Lycan
Nyx Assassin
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: Jakiro, Viper, Venomancer, Huskar, Ember Spirit, Dark Seer, Sand King, Doom, Dawnbreaker. However, this also means they are easily stunned.
Nyx Assassin
* Nyx Assassin's skillset is mostly single-targeted, therefore he will have difficulties against heroes with illusions and summons: Naga Siren, Broodmother, Lycan, Visage, Phantom Lancer. And to make things worse, Nyx Asassin is not a common Battle Fury, Maelstrom, Mjollnir, Gleipnir or Radiance wielder to counter this problem.
Nyx Assassin
* 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.
Nyx Assassin
* Nyx Assassin might not kill Abaddon with his nuke, but a support Abaddon will struggle to protect an ally from him.
Nyx Assassin
* 
Rage allows Lifestealer to freely attack Nyx Assassin and hunt him down if Vendetta is on cooldown. Nyx Assassin cannot counter Rage with Spiked Carapace because Rage gives Lifestealer spell immunity. And besides Vendetta, Nyx Assassin has no other way of dealing damage to Lifestealer while he is spell immune.
* 
Open Wounds from Aghanim's Shard allows Lifestealer to severely slow down Nyx Assassin while also allowing his team to recover themselves while attacking Nyx Assassin. Open Wounds can also fester and spread if Nyx Assassin takes enough damage that will trigger the spread while he is affected with Open Wounds.
* 
Infest combined with an ancient creep makes Nyx Assassin an easy target to surprise with Dust of Appearance or a 
Gem of True Sight. Aghanim's Scepter upgraded Infest can also allow Lifestealer to infest, disarm and freely attack Nyx Assassin from within. and Nyx Assassin cannot counter this with Spiked Carapace because Lifestealer is invulnerable while attacking the infested enemy hero from within.
* Overall, any attempt for Nyx Assassin to gank and kill Lifestealer will hurt Nyx Assassin more than Lifestealer.
Additional:
* Like with Juggernaut's Blade Fury, Rage allows Lifestealer to freely attack Nyx Assassin and hunt him down if Vendetta is on cooldown. Nyx Assassin cannot counter Rage with Spiked Carapace because Rage gives Lifestealer spell immunity. And besides Vendetta, Nyx Assassin has no other way of dealing damage to Lifestealer while he is spell immune.
* Open Wounds from Aghanim's Shard allows Lifestealer to severely slow down Nyx Assassin while also allowing his team to recover themselves while attacking Nyx Assassin. Open Wounds can also fester and spread if Nyx Assassin takes enough damage that will trigger the spread while he is affected with Open Wounds.
* Infest combined with an ancient creep makes Nyx Assassin an easy target to surprise with Dust of Appearance or a Gem of True Sight. And similarly to Juggernaut's Omnislash and Swiftslash from Aghanim's Scepter, Aghanim's Scepter upgraded Infest can also allow Lifestealer to infest, disarm and freely attack Nyx Assassin from within. And Nyx Assassin cannot counter this with Spiked Carapace because Lifestealer is invulnerable while attacking the infested enemy hero from within.
* Like with Juggernaut, any attempt for Nyx Assassin to gank and kill Lifestealer will hurt Nyx Assassin more than Lifestealer.
Lycan
* Heroes with summons: Lycan, Broodmother, Visage, Nature's Prophet, Warlock.
Lycan
* 
Guardian Angel completely negates all of Lycan's damage since Lycan mainly deals physical damage.
* 
Purification can also be a problem for Lycan, as Purification deals damage around the target, which poses a problem for him and his summons.
Nyx Assassin
* Heroes who can drain mana can make Omniknight useless after he uses one or two abilities: Lion, Anti-Mage, Nyx Assassin.
Nyx Assassin
* 
Corrosive Skin minimizes the damage from Impale and Mind Flare, and anything else Nyx Assassin tries to throw at Viper.
* Nyx Assassin cannot survive several poison damage-over-time output from 
Poison Attack, 
Nethertoxin, Corrosive Skin and 
Viper Strike, not even while he has Spiked Carapace active. And to make things worse, Nyx Assassin is not a common 
Silver Edge wielder to counter this problem at all.
Additional:
* Corrosive Skin minimizes the damage from Impale and Mind Flare, and anything else Nyx Assassin tries to throw at Viper.
* Nyx Assassin cannot survive several poison damage-over-time output from Poison Attack, Nethertoxin, Corrosive Skin and Viper Strike, not even while he has Spiked Carapace active. And to make things worse, Nyx Assassin is not a common Silver Edge wielder to counter this problem at all.
Lycan
* Heroes who do not have nor rely on passive abilities make Nethertoxin much less effective: Clinkz, 
Pugna, Nature's Prophet, Dark Seer, Lycan, Tusk
Lycan
* 
Charge of Darkness allows Spirit Breaker to catch up to Lycan after he uses Shapeshift.
Additional:
* Vision from Charge of Darkness will easier to catch Lycan Shapeshift and Charge of Darkness out of reach Lycan Summon Wolves and Lycan's other creeps. Until upgrade Aghanim's Scepter faster catching Lycan Shapeshift.
Lycan
* Heroes with summons and illusions as Spirit Breaker has no strong AoE capabilities to deal with them: Chaos Knight, Phantom Lancer, Terrorblade, Naga Siren, Broodmother, Warlock, Visage, Nature's Prophet, 
Shadow Shaman, Lycan, Wraith King.
Lycan
* Heroes with summoned units don't fare well against Dawnbreaker. (Phantom Lancer ,
Beastmaster ,Lycan).
Nyx Assassin
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: Jakiro, Viper, Venomancer, Huskar, Ember Spirit, Dark Seer, Sand King, Doom, Dawnbreaker. However, this also means they are easily stunned.
Nyx Assassin
* Spiked Carapace can stop Dawnbreaker's Solar Guardian which will eliminate her global presence and limits her movement around the map.
Additional:
* Spiked Carapace interrupts 
Starbreaker before Dawnbreaker has her Aghanim's Shard, as well as 
Solar Guardian during the initial channel, making her ineffective at joining and dealing damage in teamfights.
* The slow projectile and damage over time effect of 
Celestial Hammer makes it easy to stun Dawnbreaker if she attemps to engage or chase.
Lycan
* Heroes that heavily depend on illusions or summons, (Naga Siren, Terrorblade, Phantom Lancer, Lycan,...) are vulnerable to Sleight of Fist and even more so if Ember Spirit has Battle Fury.
Nyx Assassin
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: Jakiro, Viper, Venomancer, Huskar, Ember Spirit, Dark Seer, Sand King, Doom, Dawnbreaker. However, this also means they are easily stunned.
Nyx Assassin
* With Vendetta, Nyx Assassin can move closely to Ember Spirit when he's farming with his Flame Guard and use Spiked Carapace with Impale to provide a reliable and long disable.
Additional:
* Spiked Carapace can be easily triggered by 
Flame Guard or Battle Fury, setting up a deadly Impale.
Lycan
* Heroes with summons and illusions can find themselves easily bested by Lina, like Broodmother, Nature's Prophet, Chen, Terrorblade, Naga Siren, Visage, Wraith King, Lycan, Phantom Lancer, Shadow Shaman.
Nyx Assassin
* Heroes who build Black King Bar as either core or situational item will be able to fight back against Nyx Assassin and freely attack him as Spiked Carapace cannot pierce spell immunity at all: Axe, Broodmother, Dawnbreaker, Enigma, Huskar, Jakiro, Legion Commander, Lina, Luna, Lycan, Slardar, Slark, Troll Warlord, Witch Doctor.
Nyx Assassin
* Mind Flare does tons of damage against Lina because of her high intelligence.
* Vendetta can deal heavy damage to Lina while also burning her mana, preventing Lina from casting her abilities.
* Spiked Carapace can easily be used to counter Lina's abilities because of their long cast animation, and could probably kill Lina outright if Laguna Blade is reflected. However, Lina can counter this with 
Eul's Scepter of Divinity, a common item on Lina.
Lycan
* Shapeshift allows Lycan to escape from Upheaval with maximum movement speed.
* Warlock doesn't have a good solution to deal with Lycan's wolves from Summon Wolves.
Nyx Assassin
* Impale and Spiked Carapace interrupts Upheaval with ease.
* Warlock's low health pool, mobility, and high intelligence gain makes him a prime target for Nyx Assassin's burst damage.
Lycan
* Shapeshift allows Lycan to get close and disable Marksmanship.
* Shapeshift also makes him immune to slows like Drow Ranger's Frost Arrows.
Additional:
* The Wolves's speed causes the knockback from 
Gust to be ineffective.
* Drow Ranger lacks escapes and loses her 
Marksmanship when someone is near her. Lycan can take advantage of these weaknesses of Drow Ranger.
Nyx Assassin
* Nyx Assassin has a lot of burst damage from his Impale, Mind Flare, 
Dagon, and the bonus damage from Vendetta. All of this damage is enough to kill Drow Ranger.
* Nyx Assassin is usually invisible most of the time thanks to his ability Vendetta, which allows him to gank Drow Ranger easily.
* However, Gust is extremely dangerous for Nyx Assassin, as it's silence can render Nyx Assassin unable to lock down Drow Ranger. And if Gust hits Nyx Assassin while he is invisible with Vendetta, Drow Ranger will be able to detect him and foil his ganking attempts on her because Gust reveals invisible units.
Lycan
* Shapeshift is useful for killing or escaping Silencer.
* Summon Wolves, can be used to hunt and harass silencer - even when Lycan himself can't fight.
Nyx Assassin
* 
Last Word is extremely easy to reflect with Spiked Carapace for large amounts damage, due to triggering when Nyx Assassin casts a spell, but can still silence Nyx Assassin. It also has the added bonus of dealing more damage the more Intelligence Silencer has.
* 
Glaives of Wisdom quickly builds Silencer's Intelligence, making him a particularly prime target for Mana Burn.
* Silencer rarely builds survivability items, nor is he able to steal much Intelligence while surrounded by his team, and so is an excellent target for Vendetta.
* Silencer has no reliable way of dealing with a burrowed Nyx, and also lacks the ability to prevent Nyx from escaping with Vendetta,
Additional:
* Silencer is rather squishy and has poor mobility without items, making him an easy target for Nyx.
* Silencer's intelligence steal ability is a complete disadvantage against Nyx Assassin as Mind Flare will deal increasing damage for each point of intelligence Silencer has stolen, turning Silencer's intelligence steal against him.
Lycan
* Lycan can clear waves of Chen's creeps with his wolves from Summon Wolves, especially once Lycan takes +2 Wolves summoned talent. And even though Chen can convert one of his wolves with 
Holy Persuasion, Lycan can counter this by buying 
Helm of the Overlord to regain control of it. Uncontrollable wolves summoned from Aghanim's Shard upgrade Summon Wolves cannot be converted with Holy Persuasion.
* Shapeshift allows him to chase down Chen and kill him easily.
* 
Howl can reduce attack damage of both, Chen and his creeps.
Nyx Assassin
* Heroes with either magical, physical or pure damage burst can often kill Chen or his allies before he can use Hand of God: Lina, Luna, 
Techies, Shadow Fiend, Pugna, Nyx Assassin.
Lycan
* Windranger tends to fare badly against high mobility heroes that can easily dodge Powershot, close the gap on her when she uses Windrun or escape from Focus Fire's reach. Examples of such heroes include Spirit Breaker, Lycan, 
Storm Spirit, 
Earth Spirit, Void Spirit, Slark and others.
Nyx Assassin
* Many of Nyx Assassin's abilities are good against Windranger.
* Impale is great for stunning Windranger and allowing additional disables to be landed.
* Mind Flare is useful against Windranger's decent intelligence growth.
* Spiked Carapace is easy to use against Powershot.
* Vendetta allows Nyx Assassin to sneak up on and deal massive damage to Windranger without giving Windranger a chance to use Windrun to evade it.
* Nyx Assassin's item build allows him to easily deal with Windranger.
Lycan
* Heroes who can summon illusions and summons because Terrorblade has no abilities to deal with multiple enemies at once outside Reflection: Shadow Shaman, Naga Siren, Broodmother, Lycan, Enigma, Chaos Knight, Phantom Lancer, 
Shadow Demon, Dark Seer, Nature's Prophet, 
Invoker, 
Morphling, Visage, 
Grimstroke with Aghanim's Scepter.
Nyx Assassin
* Nyx Assassin deals large amounts of pure damage with Vendetta and magical damage with Impale and Mind Flare, allowing him to ignore Terrorblade's armor and burst his low health pool down before he can use 
Sunder.
* Nyx Assassin commonly buys 
Urn of Shadows, Dagon and 
Meteor Hammer which deal magic damage that ignore Terrorblade's armor.
* However, Terrorblade is a natural Eye of Skadi and Black King Bar wielder, and once he gets those items, Nyx Assassin's solo kill potential against Terrorblade will be gone.
Lycan
* You can easily kill a squishy 
Sniper, due to your high movement speed and his lack of escape.
Nyx Assassin
* 
Assassinate is easy to reflect with Spiked Carapace for massive damage.
* 
Shrapnel's area damage can set up an easy stun with Spiked Carapace, especially when combined with Vendetta.
* In the early game, Sniper's low health pool and high intelligence makes him easy prey for Nyx Assassin.
Lycan
* Shapeshift increases Lycan's movement speed and renders him unslowable, allowing him to easily avoid and escape Ancient Apparition's abilities.
* Lycan has fast summons, both his wolves from Summon Wolves can do heavy damage to Ancient Apparition due to his immobility and low armor.
Nyx Assassin
* 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.
Lycan
* Any Hero with high mobility will be neutralized by dream coil: 
Queen of Pain, Storm Spirit, Ember Spirit, Lycan, 
Bloodseeker, Anti-Mage, Timbersaw.
Lycan
* A Lycan with Shapeshift can always run down Puck for a very quick kill due to its low armor. It is important to abuse as many cliffs and trees as possible to escape from a Lycan.
Nyx Assassin
* 
Illusory Orb is easy to reflect with Spiked Carapace, either stunning Puck and setting up an easy Impale or forcing a premature 
Phase Shift.
* Puck is an intelligence hero that tends to build intelligence items, making it vulnerable to Mana Burn.
* An ill-timed Phase Shift can easily set Puck up to be stunned by Impale.
* Puck's low base armor and below average agility gain mean it is always susceptible to Vendetta.
Additional:
* Nyx Assassin can take advantage of every one of Puck's weaknesses. His entire skill set is very effective in countering Puck.
* Because Illusory Orb is such a slow moving projectile, Nyx Assassin can simply walk into the orb and activate Spiked Carapace, stunning Puck and setting up an easy Impale. This can be circumvented by using Phase Shift while the orb is traveling, however, that means that Puck cannot use Phase Shift to dodge any other skill nor use it to safely blink away from a fight.
* Puck is an intelligence hero that likes to build intelligence items such as Eul's Scepter of Divinity, 
Scythe of Vyse, and Dagon. This makes Mind Flare that much more deadly against Puck.
* An ill-timed Phase Shift can turn into an easy setup for Impale.
Lycan
* Once you get a Black King Bar, squishy spellcasters like 
Zeus, Skywrath Mage and others will be probably easy to deal with.
Nyx Assassin
* 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.
Lycan
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: Beastmaster, Broodmother, Chaos Knight, Lycan, Naga Siren, Nature's Prophet, Phantom Lancer, Shadow Shaman, Terrorblade, Visage, Warlock, Wraith King.
Nyx Assassin
* 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.
Nyx Assassin
* Nyx's Spiked Carapace can reflect the damage of 
Sharpshooter, instantly killing hoodwink. Nyx can also use Vendetta to position himself in such a way to screen allies from Sharpshooter and catch Hoodwink by surprise.
Nyx Assassin
* Nyx can walk into Firefly with Spiked Carapace and stun Batrider if he has no Spell Immunity, even if Batrider is focusing on other enemy hero.
Lycan
* Howl reduces a good chunk of Marci's attack damage that she relies heavily on, and the armor reduction works better on her because of her low armor.
* Shapeshift renders Lycan immune to slow from Rebound and Unleash.
Lycan
* 
Magnetic Field is useless against melee heroes, so Lycan can attack Arc Warden without missing.
* 
Flux doesn't affect Lycan that much, because Shapeshift grants immunity to slows and because he is never alone.
* If their 
Tempest Double has been called, Lycan can still kill Arc Warden before the double expires.
Nyx Assassin
* Impale and Spiked Carapace can be used to cancel Dismember easily, and can even do so when Pudge uses it on Nyx Assassin, if timed correctly.
Lycan
* Heroes who rely on physical damage output to be effective will fare badly against Muerta's 
Pierce the Veil: Phantom Assassin, Terrorblade, 
Drow Ranger, 
Lifestealer, Anti-Mage, 
Alchemist, Lycan, Clinkz, Sniper.
Lycan
* Heroes with abilities that can close the gap can easily kill Muerta: Storm Spirit, Earth Spirit, Ember Spirit, Void Spirit, Lycan, Chaos Knight, Tusk.
Nyx Assassin
* Nyx Assassin's high burst damage, excellent ganking potential and multiple disables pose a threat to Muerta at all stages of the game.
* Mind Flare allows Nyx Assassin to take advantage of Muerta's high intelligence and make a short work of her low health.
* Spiked Carapace and Vendetta allow Nyx to escape or initiate well against Muerta's low mobility.
* As with most retaliation based abilities, Spiked Carapace can easily take advantage of 
Gunslinger's stray shots.
* However, Muerta is a natural Black King Bar wielder. And if she succeeds to activate it before Nyx Assassin can ambush her, he will go down very quickly against Muerta as Spiked Carapace cannot pierce through debuff immunity at all.
Lycan
* Shapeshift allows Lycan to chase down Earth Spirit.
Nyx Assassin
* Crystal Maiden has a very bad movement speed, so Impale is easy to land against her. Furthermore, even while trapped by Frostbite, Nyx Assassin can still cast Impale.
* Crystal Maiden has very low armor, so Vendetta is very effective.
* Nyx Assassin has two ways to stop Freezing Field, provided she doesn't get a Black King Bar. He can either pop Spiked Carapace and simply walk into the field, or he can use Impale to interrupt the field, since Crystal Maiden has to channel it.
Additional:
* Spiked Carapace easily interrupts 
Freezing Field.
* 
Frostbite's damage over time sets up an easy Spiked Carapace stun.
* Crystal Maiden is extremely fragile and dies quickly to Nyx Assassin's burst damage.
Lycan
* The movement speed granted from Shapeshift means that Spectre has no way to punish Lycan if he wants to splitpush or pick off supports. Furthermore, he will kite 
Haunt and cannot be slowed by 
Spectral Dagger.
* Lycan is often part of an early game push strategy which is often the best counter to Spectre because she needs a lot of time and space to come online as a late game carry.
Nyx Assassin
* Spiked Carapace stops Snapfire's 
Mortimer Kisses.
Nyx Assassin
* Mana Burn removes much-needed mana for 
Ball Lightning.
* Spiked Carapace triggers on 
Static Remnant for an easy stun.
Additional:
* Vendetta is capable of removing most of Storm Spirit's large mana pool, along with dealing heavy damage and quickly depleting his chances of escaping a gank or fight.
Nyx Assassin
* Nyx Assassin's high burst damage can be the bane of Dark Willow, as her low health makes it difficult to survive long enough to escape through Shadow Realm.
* Spiked Carapace can be triggered by walking deliberately into Bramble Maze, leaving Dark Willow stunned and defenseless.
Nyx Assassin
* The huge physical damage taken from Vendetta will force Necrophos to use Ghost Shroud, which is good for a followup with Dagon and 
Ethereal Blade, both of which are common items on Nyx Assassin.
* Using Ghost Shroud also sets Necrophos up for a Mind Flare or Impale.
Nyx Assassin
* A good Nyx can reflect Queen of Pain's Sonic Wave with his Spiked Carapace, or even initiate a gank on her in Vendetta while she farms a creep wave with Scream of Pain.
* Her strength to intelligence ratio is bad enough that he should be able to kill her without even requiring a Dagon, provided he can get his full combo off.
Lycan
* 
Keeper of the Light has a blind, which causes Lycan to miss his attacks.
Lycan
* Heroes with hastes: Dark Seer, Lycan
Nyx Assassin
* 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.
Nyx Assassin
* Nyx Assassin can simply activate Spiked Carapace while under many Invoker's abilities to stun him.
* Nyx Assassin takes advantage of Invoker's massive intelligence gain to do tons of damage using Mind Flare, as the spell does more damage based on the target's intelligence.
* Vendetta burns a large amount of Invoker's essential mana pool.
Lycan
* Lycan doesn't care much about Lich's slows thanks to Shapeshift.
* Chain Frost can bounce to the wolves that Lycan summons.
Additional:
* 
Lich possesses a lot of slows, which Lycan doesn't care about when he Shapeshifts.
* Lich has no in-built escape, which makes him a good target for Lycan.
Nyx Assassin
* Spiked Carapace reacts on any of the damage over time from Phoenix's abilities and can interrupt 
Sun Ray and 
Icarus Dive.
Nyx Assassin
* Spiked Carapace allows Nyx to get an easy long-duration stun on Weaver once he uses Shukuchi, and then he can follow up with Impale.
* Vendetta works as a great setup for both Impale and Spiked Carapace and can deal decent damage to Weaver. Additionally he can neutralize The Swarm beetles due to his invisibility duration.
Lycan
* Lycan's ultimate makes him immune to slows from Ursa's 
Earthshock as well as allowing him to outmaneuver Ursa during 
Enrage. Lycan can also easily chase down Ursa while shapeshifted, should Ursa try to flee.
Lycan
* Mirana's Leap is ineffective if Lycan uses Shapeshift. It also allows him to dodge Sacred Arrow.
Nyx Assassin
* Vendetta disables Vengeance Aura and allows him to attack Vengeful Spirit with Impale and Mind Flare.
* Spiked Carapace is easy to use against a Wave of Terror or Magic Missile.
Nyx Assassin
* Outworld Destroyer's high intelligence gain and fragility makes him an easy target for a massive Mana Burn, as well as killing him outwards with Nyx Assassin's high burst damage.
* 
Astral Imprisonment can be easily exploited by Nyx Assassin with his abilities. As long as Astral Imprisonment was not cast on Nyx Assassin, it will make an opportunity for an easy stun, either by Spiked Carapace (if Outworld Destroyer hid his allies or your allies) or Impale (if he hid himself). If Astral Imprisonment was cast on Nyx Assassin, using Spiked Carapace while banished will proc the stun after the disable, since Spike Carapace has a 0 second cast time and Astral Imprisonment deals damage right after the disable ends.
* An ill-timed 
Sanity's Eclipse and/or well timed Spiked Carapace can deal a lot of damage to Outworld Destroyer and stun him, unless Outworld Destroyer used Black King Bar beforehand.
Additional:
* Outworld Destroyer's high intelligence makes him a good target for Mind Flare.
* If timed correctly, Spiked Carapace will return the full damage from Sanity's Eclipse back to Outworld Destroyer. Even a reflected Arcane Orb can deal significant damage and make him vulnerable to a follow-up from Nyx Assassin.
* Spiked Carapace is also the perfect tool against Astral Imprisonment: if used on Nyx, he can reflect the damage back as he comes out of the prison by casting the ability while imprisoned.
Nyx Assassin
* 
Heat-Seeking Missile allow easy Spiked Carapace stuns.
* As a fragile hero that relies on mana and intelligence items, Tinker is vulnerable to Mana Burn.
* Nyx Assassin's stuns can interrupt 
Rearm and leave Tinker helpless.
Additional:
* Nyx Assassin's whole skillset is good against Tinker:
* Impale prevents Tinker from blinding Nyx Assassin or fighting back, while giving Nyx' allies time to catch up to Tinker's position.
* Mind Flare generally deals more damage to intelligence based heroes like Tinker.
* Spiked Carapace can stun Tinker at a moment of Nyx Assassin's choosing if March of the Machines has been cast. It is also quite easy to time Spiked Carapace against Heat Seeking Missiles.
* Vendetta allows Nyx to approach Tinker in the trees or wait for him in common hiding spots and deal heavy damage to his low armor.
Lycan
* Lycan relies heavily on right clicks making Untouchable very effective against him.
* If he tries to run away Impetus will do huge amounts of damage.
Additional:
* She can 
Enchant one of the wolves to her side.
* Lycan will struggle greatly to harm Enchantress through her 
Untouchable which can seriously slow down Lycan's attack speed even if Lycan is spell immune.
Lycan
* Heroes with haste can negate Enchant's slow: Weaver, Dark Seer, Lycan, 
Centaur Warrunner.
Nyx Assassin
* Vendetta can deal great damage against her. However, it requires an direct attack, so Nyx Assassin may have difficulties applying Vendetta on her.
* Enchantress's lack of mobility makes her a primary target for ganking with Vendetta.
* Mind Flare can deal a great damage against her due to being an Intelligence hero.
* Spiked Carapace can reflect Impetus and stun Enchantress.
Additional:
* Spiked Carapace reflects the damage from 
Impetus.
* Enchantress is a rather squishy hero, making her fall easily to Nyx Assassin's high burst damage.
Lycan
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* 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), Jakiro, Pugna, Doom
Nyx Assassin
* Large area-of-effect with delay or require channeling: Enigma, 
Crystal Maiden, Invoker, Shadow Fiend, Pugna, Keeper of the Light, Dawnbreaker.
Lycan
* Lycan and Weaver has abilities that allow them to move at maximum movement speed, and those abilities can't be dispelled, potentially wasting the slow from Demonic Purge.
Nyx Assassin
* Heroes with invisibility: (Riki, Clinkz, Nyx Assassin.
Lycan
* Once you get a Black King Bar, squishy spellcasters like Zeus, Skywrath Mage and others will be probably easy to deal with.
Lycan
* Heroes with single-target abilities will be overwhelmed by Lycan and his summons: Wraith King, Bane, Phantom Assassin.
Lycan
* Heroes with single-target abilities will be overwhelmed by Lycan and his summons: Wraith King, Bane, Phantom Assassin.
Nyx Assassin
* Heroes that can pick you off: Clinkz, Nyx Assassin, Puck, Riki.
Nyx Assassin
* 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.
Nyx Assassin
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: Jakiro, Viper, Venomancer, Huskar, Ember Spirit, Dark Seer, Sand King, Doom, Dawnbreaker. However, this also means they are easily stunned.
Lycan
* Heroes with low armor and little mobility, like Huskar, 
Io, etc. will also have an unfortunate fate.
Nyx Assassin
* Nyx Assassin can reflect Life Break with Spiked Carapace.
Nyx Assassin
* Some abilities deals damage from an independent source and not from the hero itself, so Nyx cannot counter them with Spiked Carapace: illusions or summoning units, 
Homing Missile, 
Nimbus, 
Mass Serpent Ward, 
Death Ward and especially Techies's mines.
Lycan
* He can send wolves to defuse 
Proximity Mines, and he can catch up Techies and kill him before they can deny themselves. Even if the suicide is successful, Lycan can still survive because of his tankiness.
Lycan
* Heroes who summon multiple units that are not spell immune. Nature's Prophet,Lycan,Beastmaster
Nyx Assassin
* Nyx Assassin's Spiked Carapace will stun Leshrac when hit by any of his AOE abilities.
* Mind Flare deals high damage due to Leshrac's high intelligence gain.
* Vendetta burns a large amount of Leshrac's essential mana pool.
Lycan
* Pugna's 
Decrepify prevents the target from taking physical damage or doing damage, which poses a huge problem for Lycan, as he mainly deals physical damage.
Nyx Assassin
* 
Nether Blast's animation makes it easy to time Spiked Carapace for a stun.
* Pugna has the largest intelligence gain in the game, making him a prime target for Mana Burn.
* Pugna needs to channel 
Life Drain, making him easy to hit with Impale.
Additional:
* Due to Pugna's incredible intelligence growth and terrible strength growth, Nyx should always be able to take you out with his combo, with or without an added Dagon. Mind Flare will deal a large amount of damage in particular, especially in the late game.
* Spiked Carapace is also a great tool versus Pugna. A good player will wait for you in Vendetta until you farm a creep wave with Nether Blast and reflect it back at you as their initiation and setup for Impale.
Nyx Assassin
* Heroes that have a weak laning stage: 
Spectre, Nyx Assassin, 
Clockwerk, Spirit Breaker, 
Omniknight, 
Pudge.
Lycan
* Void's slow is useless against Lycan by activating Shapeshift.
* Night Stalker's single target abilities (with the exception of Void upgraded by Aghanim's Scepter) is not very effective against Lycan's Summon Wolves during the early and mid game.
Lycan
* Phantom Assassin's 
Blur is a real problem for Lycan, as he relies entirely on direct attacks to deal damage.
Lycan
* Heroes with single-target abilities will be overwhelmed by Lycan and his summons: Wraith King, Bane, Phantom Assassin.
Nyx Assassin
* Heroes with heavy early and mid-game magical damage are also problematic for Phantom Assassin due to being able to easily kill her before she can gain an item advantage over them: Lina, Necrophos, Nyx Assassin, Gyrocopter, Jakiro, 
Death Prophet.
Nyx Assassin
* Heroes who are entirely reliant on dealing physical damage and/or have very little to no area-of-effect abilities will make Underlord tickle and will have no effect against him thanks to his 
Atrophy Aura, and will also be unable to ambush Underlord and his team if Underlord chooses to use 
Fiend's Gate to get to a designated point of the map: Phantom Assassin, Terrorblade, Troll Warlord, Drow Ranger, Phantom Lancer, Chaos Knight, 
Sven, Wraith King, Bounty Hunter, Alchemist, Templar Assassin, Nyx Assassin, Bane.
Nyx Assassin
* Heroes with magical or pure damage output will not have any problems against Atrophy Aura at all: Luna, Lina, Jakiro, Pugna, Bane, 
Snapfire, 
Muerta, Nyx Assassin, Enigma, Tinker, Witch Doctor, Zeus, Crystal Maiden.
Lycan
* Her 
Mana Shield is too tough for Lycan to break.
* 
Mystic Snake can hit for a massive damage once it spread between his summons.
Additional:
* Can be easily petrified despite his speed.
* Summoned wolves will be targeted by Split Shot or Mystic Snake
Nyx Assassin
* Vendetta burns a significant amount of mana on hit, and the damage from the ability drains Medusa's mana pool even further.
* Due to the passive nature of Mystic Snake and Split Shot, it can possibly proc Nyx's Spiked Carapace if he's within range of Medusa's abilities and isn't invisible.
* Medusa lacks single target damage, making Nyx with Aghanim's Scepter extremely hard to deal with if Medusa is the team's main damage source.
Additional:
* With her passive 
Split Shot, Medusa can be easily interrupted by Spiked Carapace during combat, especially during her precious 
Stone Gaze.
* Mana Burn quickly destroys Mana Shield, especially if Medusa only increases her mana pool by bolstering intelligence (which has the added bonus of increasing Mana Burn's damage).
* Uncontrollable damage from Mystic Snake and Split Shot can trigger Spiked Carapace.
* 
Medusa lacks single target damage, making a Burrowed Nyx Assassin hard to kill.
Lycan
* 
Kraken Shell grants him massive physical attack protection
* 
Anchor Smash will wipe the area, clearing Lycan's wolves.
Nyx Assassin
* Ravage's travel time allows Nyx Assassin to easily stun Tidehunter with Spiked Carapace.
* Vendetta can instantly deplete Tidehunter's low mana pool, especially in the early game, potentially preventing Tidehunter from casting Ravage.
Lycan
* Brewmaster can waste a large portion of Lycan's ultimate by putting him in Cyclone.
* Lycan has no way to stop Brewmaster from using Primal Split by himself.
* Lycan's team often tries to push towers as a group, and Brewmaster excels at winning teamfights while trying to defend a tower.
Nyx Assassin
*
Cyclone from Storm in 
Primal Split can waste Nyx's Spiked Carapace, since its duration is shorter than the Cyclone's.