* Chaotic Offering's spell immunity piercing stun can stop Black Hole's channeling. Due to this ability's large area of effect, it can be cast at a safe distance from the Black Hole. It also goes through Black King Bar and Linken's Sphere
* Fatal Bonds can be used to make Enigma's Eidolons easier to kill, potentially feeding the enemy team. Also, it's constant damage will put Blink Dagger on cooldown, potentially forcing Enigma to prematurely activate Black King Bar.
Additional:
* Chaotic Offering pierces spell immunity and is an area of effect ability, therefore it doesn't matter if Enigma buys Black King Bar or Linken's Sphere, Warlock will always be able to cancel the channeling of Black Hole.
* Enemies often get clumped up around Black Hole to hit your allies, giving you a perfect opportunity to cast Fatal Bonds, Chaotic Offering, and Upheaval on multiple enemies.

* Telekinesis has a longer range than the AoE of Black Hole for the purposes of cancelling it.
* All of Enigma's spells are useful to Spell Steal.
* Malefice is useful for interrupting channeling spells or long cast animations. Its stun duration is also amplified thanks to Spell Steal's debuff amplification.
* Demonic Conversion can be used to push or counter-push a lane.
* Midnight Pulse is useful to block an area or for team fights.
* Black Hole is very easy to steal, as it is a channeled ability. It's also one of the best ultimate abilities for team fights, and it can easily turn the fight around for the enemy team. It also does more damage and has a larger cast range thanks to Arcane Supremacy.
* A stolen Black Hole can also cancel your Black Hole.
* Aghanim's Scepter allows Rubick to potentially steal both Midnight Pulse and Black Hole, and it upgrades Black Hole to deal percentage based damage. In combination with the level 25 talent which grants spell amplification to stolen spells, and Arcane Supremecy, Rubick is one of Enigma's worst nightmares.

* 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.

* While heroes with strong mobility are able to get close or flee from Upheaval, heroes with no escaping abilities or that lack long disables will perish against Warlock. Once the Warlock Golem lands with its stun, its hardly possible to escape when he casts Upheaval. Notable examples: Huskar, Drow Ranger, Lion, Elder Titan, etc.

* Channeling heroes will not go well against Warlock, especially those who build Black King Bar as Warlock's ultimate ability stun goes through spell immunity. E.g.: Crystal Maiden, Witch Doctor, Enigma, etc.

* Rubick can steal Death Ward easily as it is a channeled ability and then use it to turn teamfight to his advantage.
* However, a skilled Witch Doctor will toggle Voodoo Restoration immediately after placing his Death Ward to prevent that.

* If Rubick can use Spell Steal to take Nethertoxin, he will be able to disable Corrosive Skin, reducing much of Viper's durability.
* He can also steal Viper Strike, which can be used to hinder a hero on your team (or multiple heroes, if Rubick has Aghanim's Scepter).

* Viper cannot interrupt heroes with powerful channeling abilities: Bane, Enigma, Shadow Shaman, Warlock

* Fade Bolt reduces damage output of Anchor Smash.
* Ravage is an easy target to Spell Steal, so always be sure to use Anchor Smash immediately after Ravage when playing against a Rubick.
* Spells stolen by Rubick are potentially stronger due to the lack of cast animations, his talents, and his passive, Arcane Supremacy.

* All of Underlord's abilities are useful for Rubick to Spell Steal.

* 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.

* Rubick's ability to steal Attribute Shift (Strength Gain) makes him extremely annoying to deal with because Rubick's shifted attributes will remain even if he steals a new spell.
* If Rubick moves enough points to strength and then steals Adaptive Strike, he will have a powerful 3-second ranged stun in his arsenal as well.
* Waveform provides a reliable nuke/escape to Rubick.
* Rubick can steal most abilities Morphling uses while Morphed, allowing Rubick to steal his own allies' abilities if the Morphling is not careful.

* Because Shadow Fiend lacks escaping mechanisms, and is dependent on fair positioning for channeling Requiem of Souls, it's easier for Warlock with his long range crowd control abilities to lock Shadow Fiend down for his team.

* Chaotic Offering's vast area-effect can destroy trees and stun Hoodwink.
* Upheaval makes retreating with Scurry difficult.

* Rubick can use Spell Steal to steal Astral Imprisonment, and if Rubick gets Aghanim's Scepter he gets 2 charges of it. This can overpower Outworld Destroyer in team fights.
* Rubick can also steal Sanity's Eclipse against Outworld Destroyer's teammates.

* Rubick is a potential counter to Bounty Hunter as he can steal his Track and use it against his invisibility, and also provide his team with more gold if the tracked hero is killed.

* Fade Bolt can hinder Jakiro's early pushing power by clearing creep waves.
* All of Jakiro's spells are great for Rubick to Spell Steal.
* Ice Path is a great spell for Rubick so steal, since Rubick has no cast time on stolen abilities, making Rubick's version of Ice Path much more reliable than Jakiro's.
* Macropyre is a great way for Rubick to farm.

* All of Treant Protector's abilities are worth stealing, and Rubick is able to cast them with no animation time.

* Burrowstrike is one of the best and easiest steals for Rubick and Sand King should be careful when playing against him - it's much better to give away Sand Storm.

* Fiend's Grip is a powerful but channeled ability, making it useful and easy to Spell Steal and interrupt with Telekinesis.
* Stolen Fiend's Grip or Nightmare combined with Arcane Supremacy allows Rubick to disable Bane's allies for a longer period of time.
* As a natural Aghanim's Scepter carrier, Rubick can steal an upgraded Fiend's Grip and deal lots of damage to Bane's allies.

* All of Vengeful Spirit abilities are very good for Rubick to Spell Steal:
* Magic Missile provides an additional nuke/disable to pair with Fade Bolt and Telekinesis, respectively.
* Wave of Terror serves as a good scouting/armor reduction skill that Rubick and his team can benefit from.
* Nether Swap complements Rubick's mobility and pairs well with other mobility items he usually builds. He can also use it to save an ally from danger.

* All of Venomancer's abilities are decent choices for Rubick's Spell Steal. Stealing Plague Wards makes them apply Poison Sting as well.

* Fatal Bonds links the Meepos together, which combined with area of effect damage or Cleave will be devastating.

* Warlock Golems do plenty of physical and pure damage to bring down Huskar when he is at low health. Warlock is always a hazard for Huskar to initiate by using Life Break, because Chaotic Offering can stun him instantly, even when Black King Bar is activated, and allows Warlock's team to gather their wit and retaliate.
* After using Life Break to jump in, Huskar will not have any means to escape Upheaval. Which since he is an attack-dependent hero, this will nullify his impact in fights.

* All of Omniknight's abilities are valuable for Rubick to Spell Steal, and Omniknight has no throwaway ability to cover his last used spell.

* Chaotic Offering can stop heroes who like to use spell immunity and teleport scrolls to safely farm during the early to mid game, since it stuns and also goes through spell immunity. Notable examples: Juggernaut, Lifestealer.

* While heroes with strong mobility are able to get close or flee from Upheaval, heroes with no escaping abilities or that lack long disables will perish against Warlock. Once the Warlock Golem lands with its stun, its hardly possible to escape when he casts Upheaval. Notable examples: Huskar, Drow Ranger, Lion, Elder Titan, etc.

* Warlock often stays back and counter-initiates by dropping his Chaotic Offering on Earthshaker and his allies.

* Channeling heroes will not go well against Warlock, especially those who build Black King Bar as Warlock's ultimate ability stun goes through spell immunity. E.g.: Crystal Maiden, Witch Doctor, Enigma, etc.

* Chaotic Offering can stop heroes who like to use spell immunity and teleport scrolls to safely farm during the early to mid game, since it stuns and also goes through spell immunity. Notable examples: Juggernaut, Lifestealer.

* Warlock can cast Upheaval when Templar Assassin uses Meld, preventing her from escaping at the right moment.
* Warlock can also send his Warlock Golem near where she used Meld, preventing escape by Blink Dagger due to the Warlock Golem's Permanent Immolation.
* Warlock's Golem's Permanent Immolation will burn away Refraction with its damage over time.

* If Rubick steals Reaper's Scythe, he can turn the powerful ultimate back against Necrophos' team. Even his other spells are useful in Rubick's hands, giving him a sustain or a weak initiation/protection tool.

* Heroes that reduce the damage that Marci can deal during her ultimate, like Razor, Rubick, Bane, Dragon Knight and Underlord.