Bloodseeker
* 
Reincarnation makes Wraith King nearly impossible to gank with Rupture.
* 
Vampiric Spirit restores Wraith King's health, reducing the effect of Thirst.
Additional:
* 
Rupture is meaningless while Reincarnation is off cooldown.
* Vampiric Spirit and Mortal Strike prevent Bloodseeker from achieving 
Thirst bonuses.
Magnus
* Even if Wraith King dies after Magnus disables him, Magnus' entire team will be slowed and vulnerable for counter-initiation.
Bloodseeker
* If Rupture is used on Abaddon, Abaddon can use Borrowed Time and easily heal for the duration of Borrowed Time by simply moving.
Additional:
* 
Borrowed Time makes Abaddon nearly impossible to gank.
* 
Aphotic Shield and 
Mist Coil prevents Bloodseeker from gaining his Thirst bonuses.
Magnus
* Any hero who can survive Magnus's initiations and manfight him: 
Huskar, 
Faceless Void, 
Weaver, 
Abaddon, 
Troll Warlord, 
Alchemist, 
Dragon Knight, 
Night Stalker, 
Viper.
Bloodseeker
* 
Guardian Angel's near invulnerability denies Bloodseeker the bonuses from Thirst, preventing him from gaining the upper hand in teamfights.
* 
Purification's pure damage makes it hard for Bloodseeker to pursue enemies, and prevents him from replenishing his health by finishing off enemies.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: 
Sven, 
Omniknight, 
Enigma, 
Luna, 
Naga Siren, 
Mars, 
Jakiro, 
Venomancer, 
Elder Titan, Faceless Void, 
Rubick, 
Keeper of the Light, 
Pugna, 
Invoker, 
Spectre, Alchemist, 
Treant Protector, 
Lina, 
Oracle, 
Zeus, 
Shadow Shaman, 
Phoenix, 
Razor, Huskar, 
Batrider, 
Kunkka, 
Tidehunter, 
Wraith King, 
Sand King, 
Medusa, 
Dawnbreaker.
Bloodseeker
* 
Mana Shield makes it very difficult for Bloodseeker to gain his Thirst bonuses.
* Rupture rarely kills Medusa through Mana Shield.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Bloodseeker
* Heroes that rely on right-clicks will find themselves unable to damage opponents seriously after being affected by Static Link, like Sven, 
Bloodseeker, and 
Juggernaut.
Magnus
* 
Plasma Field can slow Magnus during Skewer, and when combined with 
Eye of the Storm, will potentially disable his Blink Dagger, preventing him from initiating.
* 
Static Link drains the bonus damage from Empower. However, it can be broken by Skewer and/or Force Staff.
* 
Storm Surge gives Razor and his allies high mobility needed to avoid Shockwave & Reverse Polarity.
Bloodseeker
* 
Berserker's Rage will repeatedly trap Bloodseeker in a one-on-one fight.
* 
Whirling Axes (Melee) blinds Bloodseeker, causing him to miss 60% of the time, and therefore reduces his ability to gain the upper hand in teamfights.
Magnus
* Any hero who can survive Magnus's initiations and manfight him: Huskar, Faceless Void, Weaver, Abaddon, Troll Warlord, Alchemist, Dragon Knight, Night Stalker, Viper.
Bloodseeker
* Arena Of Blood prevents Bloodseeker from attacking a Ruptured target.
* Bulwark helps Mars survive Rupture ganks simply by turning towards Bloodseeker without moving.
* Spear of Mars and God's Rebuke can push Bloodseeker from Ruptured targets.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Bloodseeker
* Heroes with area heals prevents Bloodseeker from bringing enemies low, and therefore deny him his Thirst bonuses and health return: 
Necrophos, 
Dazzle
Magnus
* Heroes that have high health but little to no magic resistance are easy prey for Necrophos, as no matter how high they build their health up, Reaper's Scythe will kill them outright as long as they fall under a certain threshold, and Heartstopper Aura will deal the same amount of damage regardless, decaying their health the longer they stay within range. As such, Strength heroes like 
Chaos Knight, 
Centaur Warrunner or 
Magnus are good targets for his ultimate.
Bloodseeker
* Heroes with high armor and durability can be exceptionally hard for Bloodseeker to bring down: Dragon Knight, 
Axe
Additional:
* Bloodseeker's physical damage is unlikely to kill Dragon Knight, and therefore rarely get a chance to recover the large amount of HP from 
Bloodrage.
Magnus
* Any hero who can survive Magnus's initiations and manfight him: Huskar, Faceless Void, Weaver, Abaddon, Troll Warlord, Alchemist, Dragon Knight, Night Stalker, Viper.
Bloodseeker
* Heroes with disables that go through spell immunity can end Bloodseeker before he has the chance to do anything: Batrider, 
Beastmaster
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Magnus
* Spectre disables Magnus' Blink Dagger using her ultimate, and later into the game can usually outlive Reverse Polarity's duration.
Additional:
* Spectre can use 
Haunt to intercept and disrupt Magnus's initiation attempts.
* 
Spectral Dagger can severely slow down Magnus after he uses 
Skewer.
* Magnus often travels alone when he is trying to initiate, so 
Desolate can be very effective against him.
* In late game, Spectre can survive 
Reverse Polarity initiation thanks to 
Dispersion.
Magnus
* Magnus has very mediocre damage against Alchemist, because he can survive the stun duration of Reverse Polarity with 
Chemical Rage.
Bloodseeker
* Bramble Maze greatly hinders Bloodseeker's ability to run around in teamfights and pick off dying allies.
* Shadow Realm prevents Bloodseeker from attacking dark Willow, allowing her to safely teleport away.
Bloodseeker
* Storm Spirit is invulnerable during 
Ball Lightning, allowing him to zip away from any ganking attempts with Rupture.
* Ball Lightning also prevents Bloodseeker from chasing down an injured Storm Spirit, or catching him in Blood Rite.
Additional:
* Storm Spirit is invulnerable during Ball Lightning, rendering Rupture ineffective against him.
Bloodseeker
* 
Fire Remnant allows Ember Spirit to escape while Ruptured.
Additional:
* Fire Remnant allows Ember Spirit to escape Bloodseeker while Ruptured.
Bloodseeker
* Any Hero with high mobility will be neutralized by dream coil: 
Queen of Pain, 
Storm Spirit, 
Ember Spirit, 
Lycan, Bloodseeker, 
Anti-Mage, 
Timbersaw.
Magnus
* 
Illusory Orb serves as a good scouting tool whenever Magnus is hiding in the trees, allowing Puck to warn its allies and disrupt his initiation attempts.
* 
Phase Shift allows Puck to dodge Shockwave when timed correctly.
* Even after Magnus successfully uses Reverse Polarity and Skewer Puck's teammates, Puck can usually counter-initiate using both 
Waning Rift and 
Dream Coil.
* Magnus cannot use Skewer when he is affected by Dream Coil, making him vulnerable to follow-up disables.
* Puck usually gets its own 
Blink Dagger as well, which makes it harder to lock down unless Magnus commits Reverse Polarity only for Puck.
Bloodseeker
* Heroes who are strong against mobile heroes: 
Disruptor, Bloodseeker, Kunkka, Keeper of the Light.
Bloodseeker
* Voodoo Restoration heals to counter Bloodseeker's Thirst.
* Rupture is generally useless against Witch Doctor while he is staying on Death Ward.
* Although Witch Doctor needs to be careful as 
Blood Rite can interrupt Death Ward.
Bloodseeker
* 
Waveform ignores Rupture's damage, letting Morphling escape unharmed.
* 
Attribute Shift (Strength Gain) makes it very hard for Bloodseeker to kill Morphling or gain his Thirst bonuses, since Morphling can use it to sustain damage while trading attacks when Ruptured.
* Morphling usually builds 
Linken's Sphere, which blocks Rupture.
Additional:
* Morphling can escape from Rupture using Waveform.
* Morphling is a typical 
Manta Style carrier, which can be used to dispel the silence from Blood Rite.
Magnus
* Similar to Night Stalker, Venomancer can simultaneously scout Magnus hiding in trees and put Blink Dagger on cooldown with 
Plague Ward, which gives Magnus problems when trying to blink in and initiate.
Additional:
* Venomancer can simultaneously scout Magnus hiding in trees and putting Blink Dagger on cooldown with Plague Wards, which makes Magnus real problems to blink and initiate.
Bloodseeker
* Snowball negates Rupture and protects Tusk allies when Ruptured.
Magnus
* All of Magnus's spells are perfect for Rubick to steal, especially Reverse Polarity for a counter-initiation.
* 
Telekinesis is one of the best instant-disables in the game, completely ruining Magnus's initiation.
Additional:
* Reverse Polarity, if stolen, can counter-initiate Magnus's team and put them at a huge disadvantage.
* Magnus himself is positioned at the center of teamfight after casting Reverse Polarity, and will be stunned by Rubick's stolen one most of the times.
* Bear in mind that Magnus will usually cass Skewer or 
Shockwave after he casts the ultimate, so the time windows left for steal can be short.
* Shockwave allows Rubick to farm fast, and also deals decent AoE damage in teamfights.
* 
Empower can be casted on the carry (especially affective if melee) on Rubick's team to accelerate their farm or amplify their damage in fights.
* Skewer could be used to displace enemy or escape from danger.
* Telekinesis can relocate the enemy in front of Rubick for Skewer.
* With Quick Cast enabled, Rubick can stop the enemy Magnus with careful prediction using Telekinesis to interrupt 
Horn Toss - Skewer combo.
Bloodseeker
* 
Time Walk negates Rupture's damage.
* 
Chronosphere prevents Bloodseeker from running down and picking off weak enemies during teamfights.
Additional:
* Time Walk will not make Rupture deal damage for the distance jumped and can be used to quickly escape from Blood Rite.
Magnus
* Any hero who can survive Magnus's initiations and manfight him: Huskar, Faceless Void, Weaver, Abaddon, Troll Warlord, Alchemist, Dragon Knight, Night Stalker, Viper.
Bloodseeker
* Heroes with gap-closing abilities who attempt to use them for escaping Bloodseeker will suffer serious damage from Rupture: 
Phantom Assassin, Anti-Mage, Faceless Void, 
Riki, 
Slark, 
Spirit Breaker.
Magnus
* If Luna can use 
Eclipse in anticipation, Magnus will be killed before he can even manages to cast Reverse Polarity.
* 
Aghanim's Scepter upgraded Eclipse is a very good counter-initiation tool against Magnus when he casts Reverse Polarity, granted as long as Luna can cast it from safe distance.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Magnus
* 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.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Bloodseeker
* Heroes with illusion and clone abilities may confuse Bloodseeker, causing him to waste time in fights: 
Phantom Lancer, Chaos Knight, 
Arc Warden
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Bloodseeker
* Heroes with high armor and durability can be exceptionally hard for Bloodseeker to bring down: Dragon Knight, Axe
Magnus
* Heroes that depend on disrupting fights with ability combos or big ultimate abilities are vulnerable to the long stun of Fiend's Grip: Disruptor, 
Death Prophet, Enigma, Faceless Void, Invoker, 
Lich, Magnus, Mars, Medusa, 
Outworld Destroyer, Phoenix, 
Puck, Queen of Pain, 
Shadow Fiend, Treant Protector, 
Underlord, 
Winter Wyvern, 
Witch Doctor, Zeus.
Magnus
* Any hero who can survive Magnus's initiations and manfight him: Huskar, Faceless Void, Weaver, Abaddon, Troll Warlord, Alchemist, Dragon Knight, Night Stalker, Viper.
Additional:
* Most of Magnus's abilities except Empower will trigger damage through 
Corrosive Skin.
* 
Poison Attack and 
Viper Strike can slow Magnus during Skewer, as well as putting his Blink Dagger on cooldown, preventing him from initiating or re-initiating.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Magnus
* Heroes that have an escape that doesn't disjoint projectiles: Mirana, Faceless Void, Magnus
Magnus
* 
Dark Ascension reduces vision for the enemy team, which makes it more difficult for Magnus to initiate with Blink Dagger and Reverse Polarity. It is also more likely that Night Stalker will scout out Magnus with Aghanim's Scepter and a 
Gem of True Sight, after which he can silence Magnus with 
Crippling Fear.
Bloodseeker
* Bloodseeker's Rupture turns Night Stalker mobility against him and Thirst grants movement speed bonus and vision prevents Night Stalker from initiating and re-initiating.
Magnus
* Zeus can easily find Magnus who is often hiding in the trees with 
Thundergod's Wrath and 
Lightning Bolt, which allows him to warn allies and disrupt his initiation attempts.
Bloodseeker
* As a spellcaster, silences will nullify him entirely. Some notable examples are Death Prophet, 
Drow Ranger, Bloodseeker, Disruptor and many others.
* 
Doom, as usual, fits this description nicely.
Magnus
* Disruptor can disable Magnus's Blink Dagger using 
Thunder Strike during a considerable duration, disrupting his initiation attempts.
* 
Glimpse brings Magnus back after he escapes with Skewer and/or Force Staff.
* 
Static Storm if used on a fight can prevent Magnus from using Reverse Polarity after he jumps in.
Bloodseeker
* Heroes with silences : Bloodseeker, Riki, 
Silencer.
Bloodseeker
* 
Shallow Grave prevents Bloodseeker from replenishing his health by finishing off enemies.
Bloodseeker
* Bloodseeker's Thirst, Rupture, and huge AoE silence Blood Rite can fare well against Dazzle.
Magnus
* Jakiro's abilities deal damage over time, which can disrupt Magnus's attempts to initiate with Blink Dagger and Reverse Polarity.
* 
Macropyre not only disables Blink Dagger for a considerable duration, but can also destroy Trees, revealing Magnus's cover and position.
Bloodseeker
* Heroes with good mobility to avoid Jakiro's abilities and with good chase to punish Jakiro from pushing a tower: Bloodseeker, Ember Spirit, Juggernaut, Phantom Assassin, Weaver.
Magnus
* Treant Protector can usually scout out Magnus in the trees with 
Eyes in the Forest and disrupt his initiation attempts. He can also counter Magnus' initiation with 
Overgrowth.
Bloodseeker
* 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.
Bloodseeker
* Every Meepo clone adds to Thirst's bonuses.
* Bloodseeker can chase down retreating clones when Meepo tries to cycle weaker clones away from combat.
Magnus
* Meepo is vulnerable to area damage and disables from Magnus himself as well as his team through Empower.
Bloodseeker
* Heroes that can maintain vision on Monkey King can see when he uses Tree Dance: Bloodseeker, Treant Protector with Eyes In The Forest, 
Sniper, Weaver
Magnus
* Skewer and Reverse Polarity will often push Monkey King out of Wukong's Command.
Bloodseeker
* Rupture works through 
Rolling Thunder and 
Swashbuckle, greatly reducing Pangolier's mobility.
Additional:
* Thirst provides constant sight and speed to Bloodseeker, allows him to catch up a fleeing Pangolier through all of his mobility.
* Rupture is a great threat to Pangolier, causing him to take heavy damage if he uses Swashbuckle and especially Rolling Thunder, forcing him to stop his ultimate prematurely, or keep rolling to his death.
Magnus
* Heroes with other kind of disables that pierce spell immunity can hold Pangolier in place during Rolling Thunder: Axe, Beastmaster, Enigma, Magnus, 
Pudge, Batrider, 
Bane, Winter Wyvern
Bloodseeker
* 
Windrun triggers the damage from Rupture.
Additional:
* Rupture turns Windranger's mobility against her.
* Blood Rite's silence makes Windranger totally useless, since she's extremely reliant on abilities.
Bloodseeker
* Thirst detects Mirana or her ally at low health during 
Moonlight Shadow.
* Rupture deals high damage when Mirana uses 
Leap.
Additional:
* Rupture can quickly kill Mirana if she tries to Leap away.
* Thirst detects Mirana and her allies during Moonlight Shadow.
Bloodseeker
* Heroes with illusion and clone abilities may confuse Bloodseeker, causing him to waste time in fights: Phantom Lancer, Chaos Knight, Arc Warden
Bloodseeker
* Bloodseeker's Rupture shows a clear red trail effect on the real Phantom Lancer.
* Heroes with undispellable debuffs will help identify the real Phantom Lancer through visual effects or debuff indicators, provided that it was cast on the real Phantom Lancer to begin with:
* 
Doom's Doom marks Phantom Lancer with a highly visible effect, and also silences and mutes him.
* Bloodseeker's Rupture shows a clear red trail effect on the real Phantom Lancer.
* 
Ancient Apparition's 
Ice Blast will only debuff Phantom Lancer and not his illusions.
* 
Grimstroke's 
Soulbind is undispellable.
* 
Shadow Demon's 
Demonic Purge is undispellable.
* 
Monkey King's 
Jingu Mastery is undispellable and puts a big yellow Mark over his head.
Magnus
* Empower helps Magnus' allies clear out illusions.
* Reverse Polarity and Skewer will pull Phantom Lancer along with his illusions, and reposition them together for easy nuking.
* Shockwave deals significant area damage in the early game,destroys phantoms and may even indicate the real Phantom Lancer.
Bloodseeker
* Rupture and Blood Rite locks down Timbersaw, preventing him from escaping with 
Timber Chain. However, Timbersaw may reflect a good deal of damage with 
Blade Mail.
Bloodseeker
* Blood Rite prevents Queen of Pain from escaping with 
Blink.
* Blink will trigger the extra damage from Rupture.
Additional:
* Blood Rite silences her, preventing her from initiating or escaping.
* With Thirst, even if she Blinks away, Bloodseeker can catch right up to her.
* Rupture will heavily damage Queen of Pain if she tries to Blink away.
* She is, however, one of the few heroes who can avoid the damage from Rupture if she successfully blink-walks.
Bloodseeker
* 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.
Bloodseeker
* Thirst detects Riki whenever his health is low.
* Rupture does large damage when Riki uses 
Blink Strike.
Bloodseeker
* 
Skeleton Walk is not enough to outrun Bloodseeker, and is detected by Thirst.
* Because of his low health and high damage output, Clinkz will get obliterated by Blade Mail
Additional:
* Thirst reveals Clinkz if he tries to escape with Skeleton Walk with low health. It also allows Bloodseeker to match or exceed Clinkz's speed.
* Rupture negates the mobility provided by Skeleton Walk in any attempt to escape or reposition in fights.
* Bloodseeker can easily build items to counter Clinkz, including 
Talisman of Evasion upgrades, Blade Mail, and armor items.
Bloodseeker
* 
Nether Swap triggers extra damage from Rupture.
* Blood Rite sets up while Vengeful Spirit using her Nether Swap within a timed correctly.
Bloodseeker
* Rupture ruins her only movement ability, Rebound. Combined with its high movement speed and her being unable to interrupt it once its cast, using it under the effects of Rupture will surely deal incredibly immutable damage, if not kill her.
* As a Strength hero, Marci naturally has high HP. Rupture's initial damage uses her high HP as a catalyst to deal damage depending on her current health, dealing a good amount of damage if she's full HP or forcing her to stop if she's low.
* With 
Aghanim's Shard, Bloodrage will now deal pure damage and lifesteal based on the opponent's max health. Her high HP as a Strength hero ensures that Bloodseeker will always deal significant attack damage and sustain himself a lot whenever he attacks Marci.
* If Marci doesn't build 
Black King Bar, Bloodseeker's Blood Rite will prevent her from using all of her spells which she relies quite heavily on. Her only dispel is tied to Sidekick with level 25 left talent.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Bloodseeker
* Blood Rite can potentially force him to activate Black King Bar prematurely, before pulling off a Black Hole combo.
* Bloodseeker can find an Enigma out of position and Rupture him, making it difficult to initiate properly in a team fight, as it pierces through Black King Bar.
Magnus
* Long ranged disables, especially those that pierce spell immunity, cancel Black Hole: Beastmaster's 
Primal Roar, Bane's 
Fiend's Grip, Faceless Void's Chronosphere, Magnus's Reverse Polarity, Axe's 
Berserker's Call, Pudge's
Meat Hook.
Bloodseeker
* Thirst allows Bloodseeker to see where Io relocated to, should either Io or the tethered hero have low health.
* Rupture forces Io to stay in place, preventing it from using the Tether bonus movement speed to escape.
Magnus
* Reverse Polarity pierces through 
Rage, wasting part of it's duration.
* Magnus is tanky and mobile, making it hard for Lifestealer to focus and kill him in all stages of a game.
Bloodseeker
* Bloodseeker is not affected by slows when he is affected by Thirst.
* If he sees Chain Frost is targeting him, he can easily isolate himself with the movement speed buff from Thirst so that it stops bouncing around.
* Lich heavily relies on his abilities to contribute to team fights, making Blood Rite effective against him.
Magnus
* Heroes with forced movement abilities or non-interrupting forced movement, such as 
Lion, Drow Ranger, Magnus, Mars, as they can cancel blast-off mid air, removing his ability to initiate or escape.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Bloodseeker
* Heroes with long-lasting, undispellable debuffs will pinpoint the true Naga Siren: Spirit Breaker, Bloodseeker, Witch Doctor.
Magnus
* Heroes whose attacks can affect multiple enemies at once will clear Naga Siren's illusions. Such heroes include Sven, Magnus, Dragon Knight, Luna, Medusa, Templar Assassin, 
Gyrocopter, 
Muerta.
Bloodseeker
* 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.
Magnus
* Squishy core heroes (Shadow Fiend, Sniper, etc)
Magnus
* Heroes who rely on illusions and spawns (Chaos Knight, Beastmaster, Nature's Prophet, Enigma etc.).
Magnus
* 
Shrapnel can sometimes scout out Magnus and also place his Blink Dagger on cooldown. Aside from that, Sniper likes to stay far back behind enemy lines, so it's difficult to catch him with Reverse Polarity unless you already have vision on him and can Skewer him to the rest of his team.
Bloodseeker
* Sniper's lack of mobility and escape mechanisms makes him one of the easier heroes for Bloodseeker to gank.
Magnus
* Squishy core heroes (Shadow Fiend, Sniper, etc)
Magnus
* Heroes with strong area-of-effect damage can make quick work of Chen's converted creeps and at same time gain farm: Magnus, Jakiro, Shadow Fiend, Kunkka, Luna, Dragon Knight, Medusa, Alchemist.
Magnus
* Any long duration disables that can pierce through both, Pierce The Veil and Black King Bar are devastating against Muerta: Enigma's 
Black Hole, Dawnbreaker's 
Solar Guardian, Axe's Berserker's Call, Naga Siren's Aghanim's Scepter upgraded 
Ensnare and 
Reel In from Aghanim's Scepter, Jakiro's Aghanim's Scepter upgraded Macropyre, Bane's Fiend's Grip, Pudge's 
Dismember, Batrider's 
Flaming Lasso, Beastmaster's Primal Roar, Grimstroke's Soulbind, Medusa's 
Stone Gaze, Magnus's Reverse Polarity.
Bloodseeker
* Heroes with fast movement abilities will suffer huge damage when afflicted by Rupture: Spirit Breaker, 
Earth Spirit, 
Dark Seer.
Additional:
* Rupture can deal a lot of damage to either a surged Dark Seer or his allies and prevent the target from getting into position.
Bloodseeker
* Bloodseeker's Rupture forces Slardar to stay still during fights, preventing Slardar from using Guardian sprint to move in and out of fights. This takes away the ability to initiate and re-initiate with Slithereen Crush's low cooldown. Due to the increased move speed from Guardian Sprint, Slardar can lose health at about 160% the rate of normal heroes while under Rupture. Bloodseeker's Thirst also gives him enough move speed so that he's one of the few heroes who can outrun or catch up to a Slardar during Guardian Sprint.
Bloodseeker
* Heroes with gap-closing abilities who attempt to use them for escaping Bloodseeker will suffer serious damage from Rupture: Phantom Assassin, Anti-Mage, Faceless Void, Riki, Slark, Spirit Breaker.
Bloodseeker
* Heroes with gap-closing abilities who attempt to use them for escaping Bloodseeker will suffer serious damage from Rupture: Phantom Assassin, Anti-Mage, Faceless Void, Riki, Slark, Spirit Breaker.
Bloodseeker
* 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.
Bloodseeker
* Heroes with fast movement abilities will suffer huge damage when afflicted by Rupture: Spirit Breaker, Earth Spirit, Dark Seer.
Bloodseeker
* 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:
* Rupture can turn Bounty Hunter's mobility against him, and prevents him from escaping with Shadow Walk due to the potentially heavy damage.
* Thirst can prevent Bounty Hunter from escaping with Shadow Walk should Bounty Hunter's health become low enough, as it provides True Sight.
Magnus
* Heroes with cleave or multi-target attacks can quickly take on Familiars and reduce Visage's firepower like Gyrocopter, Kunkka, Magnus and Medusa.
Magnus
* 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.
Bloodseeker
* Bloodseeker is one of the hardest counters to Slark.Thirst prevents Slark from healing in lane with 
Shadow Dance and may set him up for a kill while in the jungle,or retreating.
* Rupture will deal damage during 
Pounce.
* 
Dark Pact cannot dispel Rupture, preventing Slark from escaping ganks.
Additional:
* Thirst stops Shadow Dance's passive health regeneration if Slark's current health is below the Thirst's visibility threshold.
* Rupture effectively diminishes Slark's mobility in battle, leaving him susceptible to AoE stuns or forcing to teleport out of the fight.
Magnus
* Any hero who can survive Magnus's initiations and manfight him: Huskar, Faceless Void, Weaver, Abaddon, Troll Warlord, Alchemist, Dragon Knight, Night Stalker, Viper.
Bloodseeker
* 
Shukuchi will trigger extra damage from Rupture.
* Shukuchi's invisibility is detected by Thirst.
* 
Time Lapse cannot dispel Rupture, preventing Weaver from escaping ganks. However, smart Weaver will buy Linken's Sphere to counter this problem for him.
Additional:
* Rupture is particularly crippling against Weaver, who relies on high movement speed from Shukuchi to fight and escape, and it cannot be dispelled by Time Lapse.
* Thirst detects Weaver through Shukuchi whenever his health is low.
* Blood Rite combined with Rupture forces Weaver to either take damage from the latter, or to get silenced for a long duration.
Magnus
* 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
Additional:
* Anti-Mage can survive against Magnus's Reverse Polarity thanks to the high magic resistance from 
Counterspell.
* Should Anti-Mage survive Magnus's Reverse Polarity and Skewer, Magnus will have exhausted most of his skills and items, preventing him from defending himself against any counter initiation or a follow-up from a blink escape.
* 
Mana Break can deplete Magnus's much needed mana.
* Anti-Mage's 
Blink will make him a very hard target or Magnus to use Reverse Polarity on, having to solo ult him later on in the game or leave him out of the Reverse Polarity.
* Overall, any attempt for Magnus to gank Anti-Mage will hurt him more than it will hurt Anti-Mage.
Bloodseeker
* Blood Rite prevents Anti-Mage from escaping with Blink.
* Blink will trigger the damage from Rupture.
* Both Blood Rite & Rupture are pure damage which can bypass Counterspell.
Bloodseeker
* Heroes with illusion and clone abilities may confuse Bloodseeker, causing him to waste time in fights: Phantom Lancer, Chaos Knight, Arc Warden
Magnus
* Using Reality Rift sets up a Reverse Polarity on Chaos Knight and his illusions.
* Shockwave and Skewer kill Phantasm's illusions quickly, as can Empower cast on a melee carry.
Additional:
* All Magnus abilities are very good against Chaos Knight's 
Phantasm illusions.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Bloodseeker
* Blood Rite makes Ezalor chose between getting off Illuminate or getting silenced for a while, as Illuminate is a channeled ability.
* Blood Rite's silence can completely take Ezalor out of a teamfight, as he relies on his abilities to be useful.
* Keeper of the Light's only mobility source, his high movement speed (via his high base movement speed and through spirit form), is entirely countered by Rupture.
Magnus
* Heroes who take a long time to become strong are in for a rough mid game, such as Outworld Destroyer, Magnus, Medusa, and Anti-Mage.
Bloodseeker
* Rupture will fully damage Void Spirit during his ultimate, removing his main escape mechanic during fights and his way to disrupt them heavily.
* Blood Rite will force Void Spirit to use Dissimilate or Astral Step or be silenced. In the latter's case, it can be dangerous when combined with Rupture.
Bloodseeker
* Damage reduction from 
Atrophy Aura prevents Bloodseeker from killing targets and gaining his Thirst bonuses.
* 
Pit of Malice's area of effect catches Bloodseeker easily, negating his speed bonus during teamfights.
* 
Dark Rift allows Underlord to transport Ruptured allies to the fountain, rendering it useless.
Bloodseeker
* Heroes with strong area-of-effect damaging and/or disabling abilities will be able to intercept Underlord and his team when they exit from Fiend's Gate: Luna's Aghanim's Scepter upgraded Eclipse, Dawnbreaker's Solar Guardian, Axe's Berserker's Call, Mars's 
Arena of Blood, Jakiro's Macropyre, 
Dual Breath and 
Ice Path, Naga Siren's 
Song of the Siren, Razor's Eye of the Storm and Plasma Field, Lina's 
Light Strike Array, 
Broodmother's Spinner's Snare from Aghanim's Scepter, Elder Titan's 
Earth Splitter and 
Echo Stomp, Alchemist's 
Unstable Concoction and 
Acid Spray, Queen of Pain's 
Sonic Wave, Dark Seer's 
Wall of Replica and 
Vacuum, Venomancer's 
Noxious Plague and 
Poison Nova from Aghanim's Scepter, Oracle's 
Fortune's End and 
Rain of Destiny from Aghanim's Shard, Bloodseeker's Blood Rite, Enigma's Black Hole and 
Midnight Pulse, Shadow Fiend's 
Requiem of Souls, Batrider's Aghanim's Scepter upgraded Flaming Lasso, 
Firefly, 
Flamebreak and 
Sticky Napalm, Ancient Apparition's Ice Blast, Sand King's 
Epicenter, 
Sand Storm and 
Burrowstrike, Gyrocopter's 
Call Down, Ember Spirit's 
Sleight of Fist, Death Prophet's 
Exorcism and 
Silence, Monkey King's 
Wukong's Command, 
Crystal Maiden's 
Freezing Field, Muerta's 
The Calling, Medusa's Stone Gaze, Zeus's 
Nimbus from Aghanim's Scepter. 
Dark Willow's 
Bramble Maze, Pangolier's Swashbuckle, Grimstroke's Soulbind, 
Ink Swell and 
Stroke of Fate, 
Earthshaker's 
Echo Slam and 
Fissure, Puck's Dream Coil and Waning Rift, Winter Wyvern's 
Winter's Curse, Magnus's Reverse Polarity.
Magnus
* Heroes with strong area-of-effect damaging and/or disabling abilities will be able to intercept Underlord and his team when they exit from Fiend's Gate: Luna's Aghanim's Scepter upgraded Eclipse, Dawnbreaker's Solar Guardian, Axe's Berserker's Call, Mars's Arena of Blood, Jakiro's Macropyre, Dual Breath and Ice Path, Naga Siren's Song of the Siren, Razor's Eye of the Storm and Plasma Field, Lina's Light Strike Array, Broodmother's Spinner's Snare from Aghanim's Scepter, Elder Titan's Earth Splitter and Echo Stomp, Alchemist's Unstable Concoction and Acid Spray, Queen of Pain's Sonic Wave, Dark Seer's Wall of Replica and Vacuum, Venomancer's Noxious Plague and Poison Nova from Aghanim's Scepter, Oracle's Fortune's End and Rain of Destiny from Aghanim's Shard, Bloodseeker's Blood Rite, Enigma's Black Hole and Midnight Pulse, Shadow Fiend's Requiem of Souls, Batrider's Aghanim's Scepter upgraded Flaming Lasso, Firefly, Flamebreak and Sticky Napalm, Ancient Apparition's Ice Blast, Sand King's Epicenter, Sand Storm and Burrowstrike, Gyrocopter's Call Down, Ember Spirit's Sleight of Fist, Death Prophet's Exorcism and Silence, Monkey King's Wukong's Command, Crystal Maiden's Freezing Field, Muerta's The Calling, Medusa's Stone Gaze, Zeus's Nimbus from Aghanim's Scepter. Dark Willow's Bramble Maze, Pangolier's Swashbuckle, Grimstroke's Soulbind, Ink Swell and Stroke of Fate, Earthshaker's Echo Slam and Fissure, Puck's Dream Coil and Waning Rift, Winter Wyvern's Winter's Curse, Magnus's Reverse Polarity.
Magnus
* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.
Magnus
* Sven is very vulnerable to chain stun such as Lion, Shadow Shaman or Magnus.
Magnus
* Magnus is not tanky and struggles against burst damage, something Primal Beast excels at in the early-to-mid game. Primal Beast is also able to out-damage Magnus's Empower and can even contribute to his Uproar stacks.
* Using Skewer to drag Primal Beast while he is trampling will count as movement and will trigger a rapid number of slams, which could prove lethal to Magnus.
Bloodseeker
* Primal Beast's abilities require movement to deal damage, making Rupture potentially deadly and debilitating. Furthermore, its initial damage based on the target's current health is devastating to a full-health Primal Beast with his high strength gain and thus high HP.
* Due to his reliance on spells, Primal Beast is vulnerable to Blood Rite's powerful silence without items to counter it.
Bloodseeker
* Heroes with disables that go through spell immunity can end Bloodseeker before he has the chance to do anything: Batrider, Beastmaster
Magnus
* Heroes with AoE abilities are a bane to Beastmaster's summons: Storm Spirit, Magnus, Pangolier.
Magnus
* Magnus cannot manfight Huskar even with Empower, 
Berserker's Blood's high attack speed and health regeneration, combined with Huskar's high health and 
Burning Spear stacks will allow Huskar to kill Magnus before he can kill him.
* From a safe distance, Huskar can surprise and counter Magnus's initiation with 
Life Break and Burning Spear.
* Burning Spear also deals damage over time, disabling Blink Dagger and preventing him from initiating or escaping.
Bloodseeker
* Huskar is often at low health, providing large Thirst bonuses.
* Life Break triggers Rupture's damage.
Additional:
* Huskar is often at low health, providing large Thirst bonuses to Bloodseeker.
* Life Break can trigger Rupture's damage.
* A self applied Bloodrage together with Blademail means it's almost suicidal for Huskar to jump on Bloodseeker with Life Break
Magnus
* Phoenix will usually be on the sidelines or further back ready to use 
Sun Ray. Even after Magnus successfully uses Reverse Polarity and skewer Phoenix's teammates, Phoenix can usually counter-initiate using all of its abilities.
Bloodseeker
* Phoenix expends health to use its abilities, making it a good target for Thirst.
* Rupture deals heavy damage against 
Icarus Dive.
Additional:
* Although Blood Rite can be easily avoided, if it does hit, its lengthy silence and pure damage can be a severe punishment for a slow, unobservant, or simply unfortunate Phoenix.
* His Rupture can turn Icarus Dive into a suicide option, and it cannot be dispelled, meaning even if Phoenix completes a 
Supernova, choosing to Dive may just cut its health back down.
* And finally, due to Phoenix's health costs, too much careless ability spamming may just put Phoenix into Bloodseeker's vision through Thirst, making it a very tempting ganking target.
Bloodseeker
*
Laser blinds Bloodseeker, preventing him from getting last hits and denies during the laning stage and preventing him from finishing off enemies.
Boots of Travel, helping him escape Bloodseeker's early ganks.
Bloodrage as the damage will be amplified while the blind prevents Bloodseeker from landing hits.
Keen Conveyance guarantees him escape from Rupture.
* Tinker always buys
* Tinker's heavy magical damage will burst down Bloodseeker during the early to mid game, as he has little health.
Additional:
* Laser can be very effective against
*
Magnus
* Tinker can break Magnus's Blink Dagger using
March of the Machines and 
Heat-Seeking Missile, therefore delaying any initiation or making Magnus use Skewer or 
Force Staff to initiate. His {Ability ID:Defense Matrix|Tinker} will decrease the duration of Reverse Polarity and can also be cast on all of his teammates with {Ability ID:Rearm|Tinker}. Tinker usually gets his own Blink Dagger as well, which makes him harder to lock down unless Magnus commits Reverse Polarity only for Tinker.