* Rubick can turn around entire teamfights if he manages to steal Reverse Polarity.
* Shockwave allows Rubick to farm pretty fast together with Fade Bolt, and also deals decent AoE damage in teamfights.
* If Rubick steals Skewer, he can use Telekinesis to displace enemies and Skewer them away.
Additional:
* 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.

* Everything Lion has is great in Rubick's kit, further amplified by Arcane Supremacy:
* Earth Spike adds a second bit of crowd control and some damage.
* Mana Drain solves a lot of Rubick's mana issues.
* Hex is one of the strongest single-target lockdowns in the game.
* Finger of Death is one of the best magical nukes in the game.
Additional:
* All of Lion's abilities are worth stealing with Spell Steal.
* Arcane Supremacy makes the disabling spells stolen from Lion very useful, allowing you to disable enemies for an extremely long time during fights or ganks.
* By using Telekinesis, Rubick can easily catch Lion out. Without any escape mechanism, Lion is helpless, especially when ganked.

* Heroes with low health: Lich, Crystal Maiden, Lion.

* 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.

* Although Finger of Death can potentially bypass Borrowed Time, Finger's delayed damage allows an Abaddon with fast enough reaction time to activate Borrowed Time and heal from Finger.
* Aphotic Shield is extremely effective against both Earth Spike and Hex, nullifying the stun or hex while preventing further damage.
* Lion's lack of escape mechanisms allows Abaddon and his allies to pursue him with Curse of Avernus.

* 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.

* Tidehunter naturally has a high health pool and thus makes it hard for Lion to burst him down. Kraken Shell further mitigates this by dispelling any disables Lion casts when Tidehunter takes enough damage.
* Gush and Ravage can both not only burst Lion down, but also catch him out and prevent him from escaping.

* Any hero with a low HP pool is easy for Tinker to nuke down: Crystal Maiden, Enchantress, Gyrocopter, Lion, Riki, Techies, Terrorblade, Necrophos, Invoker.

* 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. Tinker usually gets his own Blink Dagger as well, which makes him harder to lock down unless Magnus commits Reverse Polarity only for Tinker.

* 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.

* Nether Ward will be problematic for heavy nukers and spammers like Skywrath Mage, Lina, Lion and Invoker, but don't use Decrepify defensively against them as you'll be helping them out more than anything.

* Batrider often hides in the trees to initiate on a target. As such, he has a slight edge against heroes that have no scouting tools and cannot see him coming, such as Lion or Sven.

* 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.

* Lion lacks mobility or escape mechanisms, making him an easy target for abilities like Mirana's Sacred Arrow or Leshrac's Split Earth, or combos like Kunkka's X Marks the Spot into Torrent.

* 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.

* 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.

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

* Waning Rift prevents Lion from casting spells during team fights, effectively making him useless.
* Puck's burst damage potential through Illusory Orb, Waning Rift, and Dream Coil allows it to easily kill Lion.
* Combined with the lockdown from Dream Coil, Puck's high mobility through Ethereal Jaunt and Blink Dagger allows it to effortlessly chase Lion.
* Phase Shift allows Puck to dodge nearly all of Lion's spells, including Finger of Death.

* 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.

* 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.

* 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.

* Hex and Earth Spike do not cancel Hoodwink's ultimate, making those two abilities ineffective against her.

* 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.

* 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.

* 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.
Additional:
* 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.

* 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.

* 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.

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

* 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.

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

* While heroes with strong mobility able to get close/flee or long range disables do well against him, heroes with no escaping abilities/lacking long disables will perish against Warlock. Once the {U:Warlock Golem} lands with its stun, its hardly possible to escape when he casts Upheaval. Just watch your pet burn the enemies as they try running away or blow their strongest abilities to stop your {U:Warlock Golem}. Notable examples: Huskar, Drow Ranger, Lion, Elder Titan, 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.

* 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.

* 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.

* Heroes that wish to disrupt fights with spell combos or big ultimates 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.

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

* 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.

* Lion lacks mobility or escape mechanisms, making him an easy target for abilities like Mirana's Sacred Arrow or Leshrac's Split Earth, or combos like Kunkka's X Marks the Spot into Torrent.

* 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.

* 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 who can disable Mars but cannot do any damage to him, meaning he just tanks their abilities: Doom, Magnus.

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

* 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.

* 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.

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

* Vendetta allows Nyx to sneak up on Lion and deal massive damage to him, especially when followed up with an Impale, Mana Burn, or even Dagon.
* Spiked Carapace has the potential to not only nullify Lion's damage, but also cripple and potentially deal massive damage to Lion, especially if he reflects Finger of Death.

* 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.

* 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.

* Most of Magnus' 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.