* Most Illusion based heroes (like Chaos Knight and Terrorblade) can't use their illusion beneficially against Sanity's Eclipse's high AoE burst damage.

Additional:
* Arcane Orb deals pure damage against the real Terrorblade, which allows it to bypass his high base armor.
* Arcane Orb and Sanity's Eclipse will make very short work of Terrorblade and his illusions.

* Arc Warden’s Magnetic Field allows him to defend against Terrorblade if he used Metamorphosis.
* Arc also buys a Bloodthorn or a Scythe of Vyse, which can prevent Terrorblade from using his abilities.

* Astral Imprisonment can be used to protect allies by imprisoning either them or Spirit Breaker.
* Arcane Orb will heavily drain Spirit Breaker's intelligence, rendering him almost useless and unable to cast spells. Spirit Breaker's low intelligence also means Sanity's Eclipse will deal a lot of damage to him.

* Heroes that can slow Charge of Darkness by a huge amount: Venomancer, Viper, Dazzle, Arc WardenLion

* Heroes that can protect or dispel stunned allies such as Legion Commander, Outworld Destroyer, Shadow Demon and Oracle can reduce the effectiveness of Sacred Arrow.

* Arc Warden can use his summons to prevent Sacred Arrow from hitting himself or his allies.
* Mirana doesn't build items that give armor often, so she usually can't fight against a late game Arc Warden.
Additional:
* Flux will slow and damage Mirana even after she Leaps, since she will likely not be near allies.
* Arc Warden can place Magnetic Field on an ally who has been hit by Sacred Arrow to protect them.

* Arcane Orb deals pure damage, effectively bypassing Morphling's high armor from Attribute Shift (Agility Gain).
* Sanity's Eclipse is more effective against a low health and mana pool Morphling, enabling Outworld Destroyer to burst Morphling down before he can shift to Strength.
Additional:
* Arcane Orb deals high damage regardless of Morphling's high armor from Attribute Shift (Agility Gain).
* Because of Morphling's very low intelligence gain and base intelligence, Sanity's Eclipse will almost always be effective against Morphling.

* Arc Warden can counter Morphling's strong pushing capabilities by using Magnetic Field to protect buildings.
* Arc Warden also often builds an Orchid Malevolence or Bloodthorn, which can prove dangerous for Morphling.
* Arc Warden can easily break Linken's Sphere with Flux and then slow him with Spark Wraith, making Arc Warden's Tempest Double a legitimate threat as well.

* Astral Imprisonment prevents Legion Commander from killing her opponents in Duels.
Additional:
* Outworld Destroyer can save an ally hero caught by Duel with Astral Imprisonment, and he can inflict heavy damage on Legion Commander with Arcane Orb to aid his ally. However, if he gets caught, he is unlikely to survive the duel, due to his lack of durability.

* Magnetic Field prevents Legion Commander from getting wins with Duel.
Additional:
* Magnetic Field prevents Legion Commander from easily gaining wins with Duel.

* Heroes with pure damage can kill Huskar when he inevitably gets low on health: Outworld Destroyer, Silencer.

Additional:
* Outworld Destroyer can dodge Life Break with Astral Imprisonment, leaving him unharmed while Huskar loses HP.
* Sanity's Eclipse can deal massive damage to Huskar before he builds up his Berserker's Blood stacks due to Huskar's low mana pool.

* Heroes with illusions can overwhelm Huskar: Phantom Lancer, Anti-Mage, Arc Warden, Chaos Knight.

* Arcane Orb's constant pure damage output is devastating to Dragon Knight.
* Dragon Knight's relatively low mana pool leads to heavy damage from Sanity's Eclipse, which also bypasses his armor.

* He can use either his own or his double's Flux to bypass the spellblock from Linken's Sphere, using the leftover Flux + Spark Wraith to slow Medusa's already low move speed to a crawl.
* Arc Warden has a farming advantage with double Hand of Midas, and can generally bully Medusa with other items that benefit from duplication.

* Arcane Orb's pure damage ignores Mars' Bulwark.
* Astral Imprisonment can be used to stop Mars from being disruptive or save allies from his abilities.
* Sanity's Eclipse deals high damage to Mars, due to his low intelligence pool.

* Magnetic Field makes Impetus miss; if Enchantress decides to enter the field, she is giving up bonus damage since Impetus deals greater damage at higher distance away from targets.

* Arcane Orb's pure damage ignores Timbersaw's Reactive Armor.
* Astral Imprisonment, if timed correctly, can interrupt Timber Chain, preventing him from escaping.
Additional:
* Arcane Orb deals constant pure damage, which bypasses Timbersaw's Reactive Armor.
* Sanity's Eclipse can hit targets inside Astral Imprisonment, which helps Outworld Destroyer finish off Timbersaw before he escapes with Timber Chain. It can also drain his mana, limiting his ability to escape should he survive.

* Sonic Wave is a bad choice in abilities if he and the Tempest Double both use Blade Mail to reflect the damage to Queen of Pain, potentially killing her outright if her health is low enough.
* Magnetic Field protects himself or his ally from Queen of Pain's attacks unless she has Monkey King Bar.
* One more advantage of Tempest Double is that he can deny himself if he is close to death with Shadow Strike's debuff.

* Astral Imprisonment can allow Outworld Destroyer to save himself or allies from Kunkka's full kit.
* Sanity's Eclipse deal a large amount of damage, as Kunkka's mana pool is much smaller than Outworld Destroyer's.
* Arcane Orb deals pure damage, shredding through Kunkka and his team even with Ghostship's buff.

* Outworld Destroyer's pure damage from Arcane Orb can go through Cold Embrace.
* Outworld Destroyer can negate the healing from Cold Embrace using Astral Imprisonment, and steal mana while doing so.
* Outworld Destroyer's damage during Winter's Curse is reduced due to Arcane Orb being unable to target allies.
Additional:
* Winter Wyvern must never put her allies in Cold Embrace against Outworld Destroyer as Arcane Orb will continue to deal damage to the defenseless hero.
* Arcane Orb does not hit his allies when he is taunted by Winter's Curse, making it weak against allies, but strong versus enemies.
* Astral Imprisonment can protect a target inflicted with Winter's Curse.

* The pure damage provided by Arcane Orb is a great addition for killing Ember Spirit.
* Astral Imprisonment fully negates all magic damage of Flame Guard and Searing Chains and will temporarily save himself from Sleight of Fist's physical damage, and Ember Spirit is not a hero that can counter these skills.

* Sanity's Eclipse does massive damage to Wraith King who naturally has a low mana pool and typically doesn't build items to increase it.
* Wraithfire Blast's slow projectile speed makes it easy to avoid using Astral Imprisonment.

* Arc Warden can turn Puck's Phase Shift ability against him by using Spark Wraith, ensuring it to hit. To make this worse, Arc Warden can do it twice with his Tempest Double.
* Flux is also an instant spell (and therefore unavoidable) with a heavy slow and damage over time, which disables Blink Dagger for a certain period of time.

* Kraken Shell's dispel does not restore mana lost through Astral Imprisonment, and the stolen mana can really hurt Tidehunter's ability to initiate
* Arcane Orb high pure damage ignores Tidehunter's Armor, and is barely affected by his Kraken Shell's damage block
* It is also completely unaffected by Anchor Smash, due to it relying on Outworlds Mana pool
* Sanity's Eclipse is effective on Tidehunter's poor mana pool, While it is reduced by Kraken Shell, the damage reduction is negligible.

* Sanity's Eclipse deals more damage the less max mana the heroes hit by it have, making Pudge an ideal target.
* Outworld Destroyer can save allies or himself caught by Dismember or Meat Hook with Astral Imprisonment.

* Astral Imprisonment can save allies from a Black Hole combo. When upgraded with Aghanim's Scepter and Aghanim's Shard, it becomes exceedingly difficult for Enigma to land a good Black Hole against Outworld Destroyer and his team.
* Astral Imprisonment can also cancel Black Hole while Enigma does not have Black King Bar.
* Arcane Orb and Sanity's Eclipse can often make a short work out of Enigma and his Eidolons.

* Outworld Destroyer can steal more mana with Astral Imprisonment from Skywrath Mage with Shield of the Scion (granted by Aghanim's Shard). Shield of the Scion grants Skywrath Mage bonus intelligence every time he deals magic damage to an enemy hero with his abilities. The higher his intelligence, the larger his mana pool. Since Astral Imprisonment steals based on the target's max mana, Outworld Destroyer can steal much more mana from Skywrath Mage.

* Outworld Destroyer is not exceptionally dangerous to Necrohpos because of his Ghost Shroud, but his Astral Imprisonment can save his allies from Necrophos's Reaper's Scythe, though only if he uses it at the right time, If an Outworld Destroyer is nearby, Necrophos should not use Reaper's Scythe unless he has banished himself, or has banished two heroes within 15 seconds

* Tempest Double, Magnetic Field's attack speed bonus, and Arc Warden's high attack range will easily destroy a Phoenix using Supernova much faster than usual.
* Phoenix is very weak against pushers, especially those like Arc Warden who can kill him easily, as his skillset works best in teamfights.
Additional:
* His Tempest Double is not an illusion, but rather a full hero unit, which effectively reduces half of the Supernova's health. His Magnetic Field can tremendously boost his attack speed, allowing him to destroy Supernova in no time even when he's affected by Fire Spirits.

* Magnetic Field evades most of Gyrocopter's attacks.

* Astral Imprisonment wastes Borrowed Time's duration.
* Outworld Destroyer's Sanity's Eclipse can kill Abaddon before Borrowed Time triggers due to the lack of intelligence for Abaddon.

* Astral Imprisonment can be used to protect allies from Jakiro's various abilities, It can also be cast on Jakiro to break his combos (Macropyre into Ice path into Dual Breath), while at the same time, stealing his much needed mana.
* Once he gets his Scepter and Shard, not only does he get two charges, he and his allies can move while imprisoned, which allows them to leave the area of your spells
* His Astral Imprisonment/Meteor Hammer combo combined with his high pure damage can quickly decimate Jakiro, And unlike most heroes, Outworld doesn't particularly care who he targets.
* Outworld is also a common Black King's Bar carrier

* Magnetic Field lets Arc Warden or allies evade Dark Willow's shadow realm attacks. The duration of the evasion can be extended with the clone.
* Spark Wraith also exploits Dark Willow's low mobility.

* Outworld Destroyer doesn't care if Razor steals his damage because he does most of his damage through Arcane Orb.
* Astral Imprisonment can prevent Razor from using the stolen damage from Static Link or chasing with Eye of the Storm.
* Sanity's Eclipse will do a ton of damage to Razor due to his low mana pool.

* Astral Imprisonment is a versatile nuisance:
* If it is cast on a low-enough-health unit at least 1 second into Shallow Grave's duration, the Shallow Grave will end during the imprisonment, and the target will take lethal damage when released.
* It can be used remove Dazzle from the fight at a time he could have saved someone.
* It lets himself or an ally dodge all of Poison Touch's effects, for long enough to recover their Blink Dagger.

* Outworld Destroyer's pure damage will mop up Primal Split's units very quickly.

* Arcane Orb's pure damage penetrates Guardian Angel's defense.
* Astral Imprisonment's mana steal is devastating to Omniknight's already low mana pool.

* Any heroes with low mana pools will die quickly or even instantly to Sanity's Eclipse: Doom, Phantom Assassin, Troll Warlord.

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

* Astral Imprisonment protects an ally for much of Rolling Thunder's duration, especially at the lower levels. As Rolling Thunder has a considerable cast animation, an Outworld Destroyer with Blink Dagger can initiate on him and destroy his timing.

* Powerful physical hitters that can destroy Pangolier during his rolling from afar: Drow Ranger, Sniper, Templar Assassin, Arc Warden

* Arc Warden's Magnetic Field dodges all damage from Death Ward.

* Shadow Demon, Outworld Destroyer and Tusk can all save a Lasso'd teammate with their defensive spells.

* Arc Warden's Tempest Double is helpful for killing Ogre Magi who lacks AoE damage and disables.

* Heroes with illusion and clone abilities may confuse Bloodseeker, causing him to waste time in fights: Phantom Lancer, Chaos Knight, Arc Warden

* Arc Warden with his Magnetic Field will protect allies from Mass Serpent Ward.

* Ranged heroes will have a hard time hitting enemies inside Magnetic Field: Silencer, Viper.

* Outworld Destroyer's pure and magical damage is particularly effective against Axe.
* Astral Imprisonment is an excellent way to defend against an initiating Axe.
* Sanity's Eclipse deals high damage to Axe due to his low mana pool.
Additional:
* Berserker's Call bonus armor doesn't block Arcane Orb's pure damage.
* Astral Imprisonment can be used to prevent an ally or Outworld Destroyer himself from an Axe initiation.
* Axe's low mana means he's susceptible to a powerful Sanity's Eclipse.

* Heroes who can slow and kite Axe will severely inhibit his presence in fights: Bristleback, Crystal Maiden, Batrider, Arc Warden, Winter Wyvern, Clockwerk

* Primal Beast is mostly played in the offlane role, so picking a carry who can escape from him is essential. Heroes such as Troll Warlord, Lone Druid and Outworld Destroyer, or generally any carry with a stun, slow or ability to fight back will stop him from having the good start he needs.

* Any heroes with low mana pools will die quickly or even instantly to Sanity's Eclipse: Doom, Phantom Assassin, Troll Warlord.

Additional:
* Outworld Destroyer's pure damage from Arcane Orb is very effective at killing Troll Warlord quickly.
* Astral Imprisonment removes Troll Warlord from a fight for four seconds, minimizing his contribution to a teamfight, and potentially wasting over half of Battle Trance's duration.
* Troll Warlord gains a measly 1 intelligence point per level, meaning Sanity's Eclipse is especially effective, often instantly killing him.

* Any hero that can outrange Plague Ward can neutralize them without putting themselves at risk of receiving Poison Sting: Arc Warden, Chen, Clinkz, Drow Ranger, Lina, Mirana, Nature's Prophet, Pugna and Sniper.
* Special mention to heroes that outrange Plague Ward after obtaining talents that increase attack range.

* Tanky melee heroes that can easily be kited, which allows Outworld Destroyer to deal heavy damage with Arcane Orb from a distance: Sven, Underlord, Bristleback.

Additional:
* Arcane Orb 's pure damage can do great damage to Underlord.
* Sanity's Eclipse can tear down Underlord's health by a large amount, since his mana pool is very low compare to OD's high mana pool.

* Ursa struggles against heroes with strong (and especially undispellable) disables (Disruptor, Puck, Shadow Demon, Outworld Destroyer and etc).

* Astral Imprisonment can waste over half of Pierce the Veil, or protect an ally from Dead Shot's fear.
* He almost always gets two charges later on, allowing him to waste the entire duration of Pierce the Veil

* Astral Imprisonment allows Outworld Destroyer to save himself or his teamates during Omnislash.
* Juggernaut's low mana from his low intelligence gain means that he'll take a lot of damage from Sanity's Eclipse.

* Magnetic Field protects Arc Warden and allies from Drow Ranger's ranged attacks. She most likely will not enter the field since she will lose Marksmanship's bonus agility.
* Beware however, as Marksmanship procs will still hit since they have True Strike, so the most damaging arrows will still hit you inside Magnetic Field.
Additional:
* Flux along with Spark Wraith allows Arc Warden to quickly burst down Drow Ranger due to her low health.
* However, Drow Ranger can bypass Magnetic Field's evasion bonus thanks to Marksmanship.

* Outworld Destroyer's pure and magical damage is particularly effective against Earthshaker.
* Astral Imprisonment catches Earthshaker while he blinks in, preventing him from executing his combo.
* Earthshaker has mana troubles, and Outworld Destroyer's abilities can press this by stealing intelligence comes from Arcane Orb, therefore depleting his mana pool and mana regeneration.
* Sanity's Eclipse deals high damage to Earthshaker, due to his low intelligence and mana pool.

* Outworld Destroyer can disrupt Slark's attacks with Astral Imprisonment either by banishing Slark or his target.
* Slark's low heathpool means he will die quickly to Arcane Orb if he is directly attacked by Outworld Destroyer
* Slark has low intelligence gain, making him easy to finish with Sanity's Eclipse if he tries to run with Shadow Dance
Additional:
* Arcane Orb deals pure damage, which ignores the armor granted from permanent agility stacks.
* Astral Imprisonment can disrupt any Pounce attempt by banishing the leashed ally.
* Slark's low mana pool makes him more susceptible to Sanity's Eclipse.

* Every hero that can withstand or prevent Eclipse at level 7: Juggernaut, Riki, Clockwerk, Drow Ranger, Abaddon, Faceless Void, Weaver, Outworld Destroyer.

* Heroes that create illusions: Spectre, Shadow Demon, Phantom Lancer, Naga Siren, Chaos Knight, Terrorblade) or bring other units into the fight (such as Nature's Prophet, Lone Druid, Chen, Enchantress, Meepo and Arc Warden) can cause Eclipse to strike the illusions/summons unintentionally. However, in many cases Moon Glaives can resolve this issue and eliminate them before activating Eclipse, but that will require lots of farming for right-click items.

* Sanity's Eclipse only triggers Bristleback's passive once, and deals high damage against Bristleback's low intelligence.
* Outworld Destroyer's high burst damage is not negated by Bristleback's passive, So even if Bristleback turns his back on Outworld, Outworld Destroyer can decimate Bristleback quickly,
* If Bristleback attempts to flee, or tries to close the gap, Outworld can banish him with Astral Imprisonment, both reducing Bristlebacks much needed mana, and allowing Outworld to move in front of him, forcing him to take the full damage from his spells, This will also allow Outworld to land a devasting Sanity's Eclipse, without it being reduced by Bristleback's passive,

* Magnetic Field's evasion completely negates Sniper's attacks unless he has True Strike.
* Sniper always positions himself far away from battles, which makes him especially vulnerable for Flux and Spark Wraith.

* Flux removes Refraction charges very quickly, and Arc Warden can hit her freely with his better attack animation, speed and range. If she tries to mute in her creep wave, Spark Wraith can quickly kill the ranged creep, forcing her to stay near the melee creeps, again, allowing for easy right clicks.
* With Tempest Double, Arc Warden can easily output 1000 damage (with the stacking of Flux and Spark Wraith and kill Templar Assassin within seconds. She cannot avoid this combo as Spark Wraith will still hit her in Meld.
* A good Arc Warden can destroy the item timings of a Templar Assassin, and mitigate her impact during the mid-game, when she is the strongest.
* In the late game, if Templar Assassin tries to split push with Aghanim's Scepter, Arc Warden's double can always threaten to kill her if equipped with a Bloodthorn and a Blink Dagger , or a Hurricane Pike, forcing her to have to use Black King Bar to survive.
* Quick reactions can also protect Arc Warden and his allies from Meld strike with Magnetic Field, and if equipped with a Hurricane Pike, Arc Warden can double force himself away from the attacking Templar Assassin to safety, where after her Black King Bar ends, she can die to Arc Warden's right clicks.

* Tanky melee heroes that can easily be kited, which allows Outworld Destroyer to deal heavy damage with Arcane Orb from a distance: Sven, Underlord, Bristleback.

* Heroes with hiding abilities can protect disabled allies: Outworld Destroyer, Shadow Demon, Tusk, Phoenix with Aghanim's Scepter.

* Sanity's Eclipse will likely instantly kill all illusions.

* Arcane Orb's pure damage, making Counterspell ineffective.
* Sanity's Eclipse will hit Anti-Mage while he is disabled from Astral Imprisonment, and forces him to take heavy damage due to his low intelligence.
* Essence Flux keeps Outworld Destroyer at high mana, thus greatly reducing the damage from Mana Void.
Additional:
* Counterspell doesn't work versus Arcane Orb because it does pure damage.
* Anti-Mage cannot burn all of Outworld Destroyer's mana without disables due to Essence Flux.
* Anti-Mage's Manta Style illusions are quickly destroyed by Arcane Orb.
* However, if the enemy has multiple means of removing mana, Mana Void becomes a threat to Outworld Destroyer, Anti-Mage has better mobility than Outworld Destroyer with Blink, and Counterspell blocks a large portion of the damage from Sanity's Eclipse.

* Arcane Orb deals heavy damage to both Lone Druid and the Spirit Bear.
* Astral Imprisonment can prevent the Spirit Bear from attacking, which is Lone Druid's main damage output.
* Sanity's Eclipse deals heavy damage to Lone Druid.