* Both Guardian Angel and Purification are perfect counters against Duel.
Additional:
* Purification prevents Legion Commander from killing her target, and will always hit her during Duels.
* Guardian Angel completely wastes Duel's duration, and can save an ally across the map when upgraded with Aghanim's Scepter.

* Atrophy Aura's percentage-based damage reduction greatly diminishes Legion Commander's overall damage output, even if she has won many Duels.
* Dark Rift can be used to save Underlord or his allies from Duels if properly timed.
Additional:
* Atrophy Aura makes it hard for Legion Commander to win Duels.
* Dark Rift can be used to save Underlord and his allies from a Duel.

* In the early game, Omniknight can look like an easy target for Spirit Breaker, but with Purification and Degen Aura, what could be an opportunity could quickly turn into disaster.
* Heavenly Grace can be used to counter Charge of Darkness by minimizing the damage and lowering the stun duration with status resistance.
* Spirit Breaker's Greater Bash from all sources (Charge of Darkness or normal attacks) deals lesser damage if he is within the radius of Degen Aura.
* Due to this, Spirit Breaker's damage will always be lower when targeting Omniknight.

* Pit of Malice can be cast in the path of Spirit Breaker's Charge of Darkness to cancel it.
* Dark Rift provides a way to escape from a gank for Underlord and his teammates.

* 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.

* 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.

* Slark's dependence on Pounce and close range makes him very easy to hit with Purification.
* Slark's damage, even with a high count of Essence Shift, is easily negated by Omniknight's heals and Guardian Angel.

* Heroes with AoE abilities will hit Slark in Shadow Dance: Lina, Jakiro, Underlord, Leshrac, Dark Seer, Earthshaker, Timbersaw, Crystal Maiden

* Heroes who rely strongly on melee physical damage will fare badly against Omniknight's Guardian Angel: Sven, Phantom Assassin, Juggernaut, Dragon Knight, Lycan, Ursa, Troll Warlord

* Atrophy Aura decreases Troll Warlord's damage.
* Pit of Malice helps lock down Troll Warlord.
* Battle Trance disallows Troll from running out of both Firestorm and Pit of Malice.

* Firestorm and Pit of Malice are very disruptive in team fights, completely matching Mars especially since it can all be cast inside Arena Of Blood and also does percentage-based magical damage, negating Bulwark.
* Dark Rift can save any allies of Underlord trapped in Arena Of Blood.
* Atrophy Aura allows Underlord to lane against Mars quite well since he does not have the best base damage during the early game.
* Underlord is a common carrier of both Pipe of Insight and Mekansm/Guardian Greaves, allowing his team to combat Mars in the mid to late game.

* Heroes that can save their allies can be a big problem for Mars: Dazzle, Omniknight.

* Underlord can not only cancel Marksmanship's aura, but his Atrophy Aura also decreases Drow Ranger's attack damage.

Additional:
* Atrophy Aura reduces Drow Ranger's damage significantly, as she relies on agility.

* In team fights, Guardian Angel renders Drow Ranger's physical damage useless.

* In general, melee heroes without blink mechanisms or spell immunity will have a hard time positioning against Pit of Malice: Sven, Tiny, Wraith King, Dragon Knight, Meepo, Doom, Bounty Hunter, Dark Seer, Undying, Alchemist, Legion Commander.

* Heroes who rely strongly on melee physical damage will fare badly against Omniknight's Guardian Angel: Sven, Phantom Assassin, Juggernaut, Dragon Knight, Lycan, Ursa, Troll Warlord

* Omniknight with Heavenly Grace
* Heroes that can remove the Track debuff with their skills:
* Abaddon with Aphotic Shield and Borrowed Time
* Huskar with Life Break
* Juggernaut with Blade Fury
* Legion Commander with Press the Attack
* Lifestealer with Rage and Infest
* Naga Siren with Mirror Image
* Omniknight with Heavenly Grace
* Oracle with Fortune's End and False Promise
* Phantom Lancer with Doppelganger
* Slark with Dark Pact
* Ursa with Enrage
* Weaver with Time Lapse
* Tidehunter with Kraken Shell when damage received reaches the threshold.

* In general, melee heroes without blink mechanisms or spell immunity will have a hard time positioning against Pit of Malice: Sven, Tiny, Wraith King, Dragon Knight, Meepo, Doom, Bounty Hunter, Dark Seer, Undying, Alchemist, Legion Commander.

* Guardian Angel negates most of Gyrocopter's physical АоЕ damage.
* Heavenly Grace dispels Homing Missile stun.

* Firestorm quickly kills all the treants and increases the Atrophy Aura passive.
* Pit of Malice can stop Teleportation channeling.
* Atrophy Aura greatly reduces Nature's Prophet's damage and he has no other ways of dealing damage.
* Dark Rift can counter split-pushing, which is something that Nature's Prophet relies a lot, and Nature's Prophet has very little solutions to intercept Dark Rift.

* Heavenly Grace dispels the stun from Ink Swell, and greatly reduces Soulbind's duration.
* Purification can turn the tables on enemies trying to get close to stun with Ink Swell.

* The pure damage provided by Purification is a great addition for killing Ember Spirit, as well as a good way of saving teammates.
* Guardian Angel will temporarily save his allies from Sleight of Fist's physical damage, and Ember Spirit is not a hero that will get Orchid Malevolence to counter it.

* Guardian Angel protects allies from Death Ward's physical damage.
* Purification and Heavenly Grace will most likely save teammates from dying to Maledict.

* Exorcism's damage is blocked by Guardian Angel.
Additional:
* Degen Aura reduces Death Prophet's movement speed, keeping her in range.
* Guardian Angel nullifies the physical damage from Exorcism.

* Omniknight's healing prevents allies from dropping low enough for Culling Blade. However, it can still go through all his buffs.
* Axe also enjoys getting close to allied heroes in order to damage them with his Counter Helix, which can easily be punished by Purification.

* Heroes with abilities that can save are also effective such as Shadow Demon, Dazzle, Oracle, Bane, Pugna, Tusk, Winter Wyvern, Io, Underlord, Treant Protector and Keeper of the Light.

* Guardian Angel completely negates all physical damage, including Omnislash.
Additional:
* Omnislash is blocked by Guardian Angel.

* Riki takes a lot of damage from Purification while ganking Omniknight's allies or himself.
* Heavenly Grace instantly purges the slow from Diffusal Blade, while also providing a large amount of survivability for his victim.
* Degen Aura can hinder Riki's positioning tactics and put a heavy toll on Riki's already poor movement speed.
* Omniknight can easily save his allies by using Guardian Angel in combat.

* Firestorm will easily clear Chen's creeps.
* Pit of Malice will trap Chen and render him helpless.
* Atrophy Aura gives bonus damage to Underlord for each killed creep and weakens Chen's damage.
* Dark Rift can counter Chen's pushing attempts, and he has nothing to intercept it.

* Heavenly Grace reduces Fireblast stun time and dispels Ignite.
* Purification can heal damaged hero if needed.

* Phantasms can be easily killed with Purification.
* Heavenly Grace dispels the stun from Chaos Bolt and the armor reduction from Reality Rift.
* Guardian Angel works well against Chaos Knight's overwhelming reliance on physical burst damage.
Additional:
* Purification heals a teammate targeted by Reality Rift and heavily damages Chaos Knight and his illusions in the process.
* Guardian Angel blocks all of Chaos Knight's damage for a duration.

* Global Guardian Angel will protect his allies from Spectre's Haunt, both when they are alone and in teamfights.
* Purification is a major problem for melee enemies, Spectre included, since they must be next to an enemy in order to attack. The AoE damage also allows Spectre to be singled out from her illusions.
* Degen Aura will prevent Spectre from chasing Omniknight, further exacerbated by her terrible mobility outside Haunt.

* Heroes that require burst damage to kill will be difficult for Phantom Lancer to take down: Timbersaw, Axe, Bristleback, Alchemist and Underlord

Additional:
* Firestorm is very useful for clearing multiple illusions swiftly.
* Pit of Malice will continuously disrupt many illusions, drastically reducing their damage and potency.
* Athropy Aura reduces damage of both Phantom Lancer and his illusions.

* Underlord's Atrophy Aura reduces Morphling's high base damage gained through agility shift.

* Heroes with spell immunity or pseudo-blinks which provide invulnerability: Lifestealer, Juggernaut, Omniknight, Huskar , and Tusk have spells which allow them to easily escape Dream Coil.

* In general, melee heroes without blink mechanisms or spell immunity will have a hard time positioning against Pit of Malice: Sven, Tiny, Wraith King, Dragon Knight, Meepo, Doom, Bounty Hunter, Dark Seer, Undying, Alchemist, Legion Commander.

* Heroes who rely strongly on melee physical damage will fare badly against Omniknight's Guardian Angel: Sven, Phantom Assassin, Juggernaut, Dragon Knight, Lycan, Ursa, Troll Warlord

Additional:
* Guardian Angel completely negates all of Lycan's damage since Lycan mainly deals physical damage.
* Purification can also be a problem for Lycan, as Purification deals damage around the target, which poses a problem for him and his summons.

* In general, melee heroes without blink mechanisms or spell immunity will have a hard time positioning against Pit of Malice: Sven, Tiny, Wraith King, Dragon Knight, Meepo, Doom, Bounty Hunter, Dark Seer, Undying, Alchemist, Legion Commander.

* Heroes with powerful rooting abilities will disable most of Pangolier's skill, a bonus point if it pierce spell immunity since it will also be able to stop Pangolier during his Rolling Thunder: Treant Protector, Meepo, Crystal Maiden, Dark Willow, Underlord, Naga Siren

* In general, melee heroes without blink mechanisms or spell immunity will have a hard time positioning against Pit of Malice: Sven, Tiny, Wraith King, Dragon Knight, Meepo, Doom, Bounty Hunter, Dark Seer, Undying, Alchemist, Legion Commander.

* Heroes who rely strongly on melee physical damage will fare badly against Omniknight's Guardian Angel: Sven, Phantom Assassin, Juggernaut, Dragon Knight, Lycan, Ursa, Troll Warlord

Additional:
* Purification easily catches Phantom Assassin when she jumps in to attack.
* Guardian Angel renders Phantom Assassin useless, as she depends entirely on physical attacks.

* In general, melee heroes without blink mechanisms or spell immunity will have a hard time positioning against Pit of Malice: Sven, Tiny, Wraith King, Dragon Knight, Meepo, Doom, Bounty Hunter, Dark Seer, Undying, Alchemist, Legion Commander.

* In general, melee heroes without blink mechanisms or spell immunity will have a hard time positioning against Pit of Malice: Sven, Tiny, Wraith King, Dragon Knight, Meepo, Doom, Bounty Hunter, Dark Seer, Undying, Alchemist, Legion Commander.

* Omniknight can dispel Hex or Shackles with Heavenly Grace. He can also heal teammates which you disabled. The same goes to Abaddon's Aphotic Shield .

* 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 that can nullify effects of Chronosphere: (Omniknight, Keeper of the Light with Aghanim's Scepter during daytime, Winter Wyvern), banishing him or Faceless Void (Outworld Devourer, Shadow Demon, Earth Spirit with Aghanim's Scepter) or protecting him in other ways (Dazzle, Oracle, Abaddon) can greatly limit Chronosphere's potential.

* Purification can heal allies while dealing pure damage to Sven.
* Heavenly Grace can remove Storm Hammer's debuff immediately or make it a very mediocre stun.
* Guardian Angel negate's Sven's massive damage during God's Strength.

* In general, melee heroes without blink mechanisms or spell immunity will have a hard time positioning against Pit of Malice: Sven, Tiny, Wraith King, Dragon Knight, Meepo, Doom, Bounty Hunter, Dark Seer, Undying, Alchemist, Legion Commander.

* In general, melee heroes without blink mechanisms or spell immunity will have a hard time positioning against Pit of Malice: Sven, Tiny, Wraith King, Dragon Knight, Meepo, Doom, Bounty Hunter, Dark Seer, Undying, Alchemist, Legion Commander.

* Being mostly a physical damage dealer, Sniper's effectiveness is greatly reduced by Omniknight's Guardian Angel.
* Omniknight's Degen Aura allows him to slow sniper and catch him. Sniper has to then use some escape item.
* Omniknight can also protect an ally from being finished off by Assassinate by using Purification.

* Firestorm will destroy Refraction charges very quickly.
* Firestorm will hit Templar Assassin while Melded.
* Templar Assassin has a hard time maneuvering around Pit of Malice.

* Dark Rift allows Underlord to transport allies from poison damage-over-time to the fountain.
* Underlord usually buys Pipe of Insight that gives a magic resistance to allies, inhibiting the damage from Venomancer abilities.

* Purification does great damage to Clockwerk when fighting an enemy inside Power Cogs.
* For the same reasons, Omniknight also makes a powerful ally for Clockwerk when the situation is reversed.

* Guardian Angel makes allies immune to all physical damage, effectively causing Tidebringer to do no damage.
* Purification is a powerful, pure damaging heal that can save Omniknight's allies after Kunkka's large damage.

* Omniknight: An undispellable Heavenly Grace can easily save a victim of Shadow Demon.

* Guardian Angel completely counters Winter's Curse if he is able to cast it.
Additional:
* Guardian Angel completely counters Winter's Curse, allowing his team to survive Winter Wyvern's initiation.
* Purification and Heavenly Grace are very useful against Arctic Burn and Splinter Blast as well.

* Heroes with dispels can dispel Bane's disables from their allies: Oracle, Legion Commander, Omniknight