* Night Stalker is one of the best heroes to find (and silence) Tinker in the trees during Dark Ascension.
Additional:
* Night Stalker can easily find Tinker in the trees during Dark Ascension.
* Void's mini-stun will stop Rearm and Keen Conveyance
* Crippling Fear's silence will prevent Tinker from fighting back, as Tinker relies on his spells.

* 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.

* Zeus can easily reveal Tinker's location in the trees with Thundergod's wrath.
* When Zeus has an Aghanim's Scepter, he can use his Nimbus, together with Lightning Bolt to interrupt Tinker's Keen Conveyance channelling and cancel Tinker's Blink Dagger.
Additional:
* Due to Tinker's low health pool, Zeus can easily burst Tinker down, while also cancelling Rearm.
* Once Zeus gets Aghanim's Scepter, he will gain Nimbus, which allows him to scout out Tinker on the map, especially when he is pushing lanes while hiding in the trees.

* 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.

* His global teleportation with Boots of Travel and Rearm is easily countered with Haunt, and Spectre can reach him anywhere on the map.
* He is squishy, and if alone Desolate will kill him very fast.
* Dispersion can reflect and reduce his burst damage.

* 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.

* Even though Luna has a hard time laning against Tinker because of Heat-Seeking Missile and Laser, she can win against him in late game once she buys Black King Bar, as none of Tinker's spells can bypass spell immunity.
* Lucent Beam and 0.25 Eclipse Lucent Mini-stun talent for Eclipse can be used to cancel Rearm and prevent Tinker's escape attempts with Boots of Travel. Luna can also use Lucent Beam and Eclipse if she is blinded with Laser.
* An ill-timed and ill-positioned Blink Dagger will make Tinker a very easy target for Luna's Eclipse that can quickly tear him to shreds. This can get even better if Luna buys Aghanim's Scepter and combines it with 0.25 Eclipse Lucent Mini-stun talent for Eclipse.
* However, Luna needs to approach Tinker carefully, as Tinker is a natural Scythe of Vyse wielder, and if he gets a jump on Luna first, he will be able to use it to disable and burst down Luna before she can use Black King Bar, Lucent Beam or Eclipse.
Additional:
* Even though Luna has a hard time laning against Tinker because of Heat-Seeking Missile and Laser, she can win against him in late game once she buys Black King Bar, as none of Tinker's spells can bypass spell immunity.
* Lucent Beam and 0.25 Eclipse Lucent Mini-stun talent for Eclipse can be used to cancel Rearm and prevent Tinker's escape attempts with Boots of Travel. Luna can also use Lucent Beam and Eclipse if she is blinded with Laser.
* An ill-timed and ill-positioned Blink Dagger will make Tinker a very easy target for Luna's Eclipse that can quickly tear him to shreds. This can get even better if Luna buys Aghanim's Scepter and combines it with 0.25 Eclipse Lucent Mini-stun talent for Eclipse.
* However, Luna needs to approach Tinker carefully, as Tinker is a natural Scythe of Vyse wielder, and if he gets a jump on Luna first, he will be able to use it to disable and burst down Luna before she can use Black King Bar, Lucent Beam or Eclipse.

* 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.

* Nether Ward discourages Tinker from using abilities and items due to its high damage against heavy mana usage.

* 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.

* Low health spellcasters: Lina, Witch Doctor, Tinker, Keeper of the Light, all rely heavily on their spells and are fragile heroes. They all also have avoidable spells, allowing Puck to get to them and quickly burst them down.

* 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.

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

* Heroes with 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.

* Tinker's Laser has very little effect on Jakiro.
* Tinker has to sit still for a short period of time due to Rearm, not only making it easy to catch him with Ice Path, but also by stunning him while he is Rearming, Jakiro generally spell Tinker's doom.
* With s high area-of-effect and strong damage-over-time capabilties, Jakiro can quickly burn through his Defense Matrix, and at the same time lock down his Blink Dagger. Both of which he relies heavily to survive on.

* 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.

* Anti-Mage's high mobility from Blink and tendency to build Battle Fury makes him strong against split-pushing heroes: Nature's Prophet, Tinker, and Arc Warden.

Additional:
* Tinker is fragile and vulnerable against carries like Anti-Mage.
* Mana Break burns away his mana pool and deals bonus physical damage.
* Tinker's massive mana pool makes Mana Void deal large amount of damage, and can be used to cancel a Keen Conveyance teleport.
* Blink gives Anti-Mage many options, like disjointing Heat Seeking Missiles. He can use Blink to wait out of sight for a split pushing Tinker or chase a blinking Tinker into trees.
* Tinker doesn't want any of his spells reflected back at him through Counterspell.

* 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.

* Similarly, heroes with low cooldown teleports can be afraid to split push against X Marks the Spot, such as Tinker and Nature's Prophet.
* In general, highly mobile heroes like Earth Spirit or Storm Spirit are at a disadvantage against X Marks the Spot.
* Similarly, heroes with low cooldown teleports can be afraid to split push against X Marks the Spot, such as Tinker and Nature's Prophet.

Additional:
* X Marks the Spot can be used to prevent Tinker from escape with Blink Dagger or Keen Conveyance, discourage him from snapping farm and snapping gank. However, in later game, it'll be much more difficult because Tinker can buy Black King Bar or Linken's Sphere to prevent Kunkka from placing X on him, or Eul's Scepter of Divinity to prevent the recall.

* 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.

* Heroes that can gain vision over trees to catch Tinker: Invoker, Shadow Demon, Batrider.

* 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.

* Shadow Wave provides good sustain against Tinker's spammable abilities.
* Shallow Grave can stop Tinker from bursting down a target.

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

* Rocket Flare can find Tinker if he blinks into the treeline, and Hookshot will prevent him from teleporting out.
* Battery Assault makes Tinker unable to Rearm by stunning him repeatedly.
Additional:
* Clockwerk can easily catch a split pushing Tinker with his Hookshot and prevent him from escaping with Power Cogs and Battery Assault. Clockwerk can also find a Tinker hiding in trees with his Rocket Flare.
* Clockwerk usually buys a Blade Mail, which does lots of damage to Tinker if he gets hit by his abilities (especially March of the Machines).

* Wave of Terror can reveal a Tinker attempting to hide in the trees and then Nether Swap and Magic Missile will both serve to interrupt/lock him down, should he attempt to town portal or reload.

* 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.

* 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.

* Tinker is relatively helpless against Invoker, as his Rearm and Boots of Travel can be easily interrupted by Invoker's long range disables, even if he blinks away.

* 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 has very mediocre damage against Alchemist, because he can survive the stun duration of Reverse Polarity with Chemical Rage.

* 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.

* 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.

* Storm Spirit destroys trees and ignores impassable terrains with Ball Lightning, rendering them dangerous places for Tinker to hide within.
* Ball Lightning disjoints projectile from Heat-Seeking Missile and damage from March of the Machines.
* Electric Vortex prevents Tinker from teleporting away, and Static Remnant and Overload can easily burst him down.
Additional:
* He can easily catch Tinker in the trees with Ball Lightning and kill him with Orchid Malevolence and his abilities, which deal both physical and magical damage, making them difficult for Tinker to itemize against.

* Tinker relies on his high mobility from Keen Conveyance and Blink Dagger to survive. Those items don't help him if Spirit Breaker manages to cast Charge of Darkness on him.
* Spirit Breaker can easily cancel Rearm and Keen Conveyance.

* 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.

* Tinker is an easy target for Earth Spirit to initiate on. He likes to split push lanes once he acquires Boots of Travel and Earth Spirit can jump him with his Rolling Boulder and disable him to buy enough time for his teammates to come and assist Earth Spirit.
* The huge range of Stone Remnant and Rolling Boulder enables Earth Spirit to stop Tinker from teleporting to his fountain since Tinker tends to buy Blink Dagger most of the time to escape.

* 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.

* Skywrath Mage stands perfectly on the center line against Tinker, thanks to his nuke and silence. Also, thanks to his abilities, he can quickly kill a victim, and Tinker is one of the most subtle heroes in the game
Additional:
* Skywrath Mage stands perfectly on the center line against Tinker, thanks to his nuke and silence. Also, thanks to his abilities, he can quickly kill a victim, and Tinker is one of the most subtle heroes in the game

* Meat Hook can be used to pull Tinker to Pudge while he is hiding in the trees, and a follow up with Dismember and Rot can lead to a valuable kill, as Tinker doesn't buy many survivability items.
* Flesh Heap makes it hard for Tinker to deal serious damage.
Additional:
* Pudge can Meat Hook a Tinker hiding in the trees and follow it up with Dismember and Rot for an easy solo kill, as Tinker doesn't tend to buy survivability items.
* Many stacks of Flesh Heap combined with items that give Pudge high strength and health will make it hard for Tinker to deal serious damage to Pudge.

* Tinker is heavily dependent on his abilities and Doom prevents him from using any of them.
* This becomes even worse if Doom chooses the level 25 talent {ValueColor:1|Doom applies Mute|25tal} {Symbol:Talent}, which will prevent Tinker from using items such as Blink Dagger.
Additional:
* Tinker is heavily reliant on casting his spells and Doom can disable all of his abilities and items. An Aghanim's Scepter only makes it harder for Tinker to survive.

* Any hero who can survive Magnus's initiations and manfight him: Huskar, Faceless Void, Weaver, Abaddon, Troll Warlord, Alchemist, Dragon Knight, Night Stalker, Viper.

* 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.

* 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.

* 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.

* Any hero who can survive Magnus's initiations and manfight him: Huskar, Faceless Void, Weaver, Abaddon, Troll Warlord, Alchemist, Dragon Knight, Night Stalker, Viper.

* 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.

* 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.

* 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.

* 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.

* 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.

* 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.

* Any hero who can survive Magnus's initiations and manfight him: Huskar, Faceless Void, Weaver, Abaddon, Troll Warlord, Alchemist, Dragon Knight, Night Stalker, Viper.

* 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.

* Any hero who can survive Magnus's initiations and manfight him: Huskar, Faceless Void, Weaver, Abaddon, Troll Warlord, Alchemist, Dragon Knight, Night Stalker, Viper.

* Heroes that can gain vision over trees to catch Tinker: Invoker, Shadow Demon, Batrider.

* 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.

* 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.

* 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.

* Illusion heroes, such as Naga Siren, Phantom Lancer, Chaos Knight, Terrorblade will become strong against Tinker in the late game. Without Aghanim's Scepter Tinker is forced to defensively disarm heroes with Laser, leaving illusions free to deal physical damage which Tinker's low armor makes highly effective. In addition, Mjollnir or Battle Fury, two common pickups against illusion heroes, don't work well on Tinker at all.

* 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 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.

* Press the Attack can dispel Laser's blind while providing great attack speed and health regeneration.
* Once caught in a Duel, Tinker, who completely relies on his spells to be effective, has little chances of survival with his low health pool and armor.

* Even if Wraith King dies after Magnus disables him, Magnus' entire team will be slowed and vulnerable for counter-initiation.

* 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.

* Beastmaster's Hawk can find Tinker easily while he is pushing or blinking into trees.

* Illusion heroes, such as Naga Siren, Phantom Lancer, Chaos Knight, Terrorblade will become strong against Tinker in the late game. Without Aghanim's Scepter Tinker is forced to defensively disarm heroes with Laser, leaving illusions free to deal physical damage which Tinker's low armor makes highly effective. In addition, Mjollnir or Battle Fury, two common pickups against illusion heroes, don't work well on Tinker at all.

* Illusion heroes, such as Naga Siren, Phantom Lancer, Chaos Knight, Terrorblade will become strong against Tinker in the late game. Without Aghanim's Scepter Tinker is forced to defensively disarm heroes with Laser, leaving illusions free to deal physical damage which Tinker's low armor makes highly effective. In addition, Mjollnir or Battle Fury, two common pickups against illusion heroes, don't work well on Tinker at all.

* 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.

* Heroes that have an escape that doesn't disjoint projectiles: Mirana, Faceless Void, Magnus

* Timbersaw's ability to destroy trees can be a serious problem for some heroes that use them, as either a way of enhancing their spells like Treant Protector, or heroes that tend to hide inside of them like Tinker and Monkey King.

* Illusion heroes, such as Naga Siren, Phantom Lancer, Chaos Knight, Terrorblade will become strong against Tinker in the late game. Without Aghanim's Scepter Tinker is forced to defensively disarm heroes with Laser, leaving illusions free to deal physical damage which Tinker's low armor makes highly effective. In addition, Mjollnir or Battle Fury, two common pickups against illusion heroes, don't work well on Tinker at all.

* 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.

* Any hero who can survive Magnus's initiations and manfight him: Huskar, Faceless Void, Weaver, Abaddon, Troll Warlord, Alchemist, Dragon Knight, Night Stalker, Viper.

* Tinker who can't fight multiple heroes will suffer greatly against Ransack and Earthbind.

* 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.

* 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.

* 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.

* 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.

* Rupture deals extra damage to Magnus during Skewer or Force Staff, preventing him from escaping or counter-initiating, forcing him to invest on a Linken's Sphere.

* Lifestealer's Rage makes him immune to all of Tinker's damage and debuffs.
* Lifestealer can infest a mobile ally (teams usually pick one against Tinker), which may ensure that Tinker will die if he is caught.
Additional:
* Rage will dispel Laser's blind and turns him spell immune for the duration so Tinker cannot damage him.
* Feast will quickly bring down Tinker due to being so fragile.