Omniknight/Counters

Bad against...

 * turns Omniknight into a walking creep, or completely takes out his buffed cores.
 * Doom also has access to Satyr Banisher's, which leaves enemies to few item counter builds or plays mistakes.


 * will purge.
 * will deplete Omniknight's already small mana pool.
 * Invoker's many disables will keep Omniknight's team occupied until times out.


 * comes with a built in purge AoE, but can't target Repelled units with that buff already applied.


 * deals pure damage, meaning it will pierce his Guardian Angel.
 * Outworld Devourer's intelligence steal is also devastating to Omniknight's already low mana pool.


 * will purge Omniknight's buffs from any ally who casts a single target spell against Razor.


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


 * will remove Omniknight's buffs.


 * & Last Word takes Omniknight out of the fight completely.
 * Glaives of Wisdom are a great harass vs Omniknight during the laning stages of the game, since it doesn't aggro creeps & ignores his high base armor. This skill deals pure damage, which means it can also go through his Guardian Angel.
 * Silencer's intelligence steal can also cause Omniknight to falter in the early phases as it reduces his ability to use his spells.

Others

 * In general, heroes with large magical AoE damage will fare well against Omniknight:, , , , etc..
 * Omniknight's teamfight impact can also greatly be reduced by heroes who can piece his spells with disables; such as: Black Hole, Reverse Polarity, Primal Roar, etc..
 * Omniknight's weakest stages of the game are his laning. Heroes such as and  can easily harass Omni out of a lane with their ranged slows and poison damage. Other heroes who pose a great threat are heroes with disables, such as Lion or Nyx Assassin, who can easily leave Omniknight being able to do nothing, while also depleting his low mana pool.

Items

 * and other items that can prevent the casting of spells makes Omniknight useless.
 * 's ability to purge a target of its buffs can become dangerous, as the effects of both and  are both eliminated.
 * 's cyclone can purge.

Good against...

 * Omniknight's healing prevents allies from dropping low enough for ; however, it can still go through all his buffs.
 * Axe also enjoys getting close to allied heroes in order to damage them with his, which can easily be punished by or Guardian Angel.
 * Although Omniknight can easily deal with Axe in the later stages of the game, during the laning stages Axe can easily punish a support Omniknight.
 * Caution though, Omniknight's melee & short cast ranges make him an easy target for Berserker's Call, which can easily turn the tide for the enemy.


 * s can be easily killed with.
 * Choas Knight's only defense against Omniknight, is being able to finish him off before he can get any spells off.


 * is blocked by, & makes Diffusal Blade a non factor when allies are grouped.


 * is an excellent chance for Omniknight to use.
 * wastes 's duration entirely


 * is blocked by.
 * Be careful of her though!

Others

 * Generally, heroes that rely strongly on melee physical damage will fare badly against Omniknight.
 * Most heroes that rely heavily on magic damage and have low movement speed or mobility will have trouble against Omniknight, as he can slow them down using his . Also he or a more dangerous ally can proceed without issue thanks to.

Works well with...

 * A on Clockwerk while he's fighting inside  will turn the fight in Clockwerk's favor.


 * solves Omniknight's mana problems.


 * solves Omniknight's mana problems.


 * Use on an enemy just before  to prevent that enemy from becoming invulnerable and single him out for a quick kill.


 * A successful is an easy set-up for a Purification.
 * Omniknight can also negate the self-damage of with Repel.


 * , and  can make for a very quick kill.
 * can be used as an alternative to a Black King Bar, giving Mortred much needed protection against magical nukers.


 * allows Shadow Fiend to channel in the midst of the enemy team without relying on.


 * let's Storm Spirit get close for an easy.

Others

 * Omniknight works well with all heroes, although during the laning stages it's best to pair him with allies who can do most of the work or handle themselves without him, since he offers little to nothing during this stage.
 * In general, heroes that can blink into enemy formations gives Omniknight an opening to use offensively.
 * Heroes that need a for spell immunity enjoy having Omniknight as an ally as he can either provide them more space to build the item, or allowing the would-be slot to be given to another item.

List of heroes that counter Omniknight, and list of heroes that work well with Omniknight.