* Fiend's Grip provides mana drain, which can heavily damage Mana Shield and prevent Medusa from using Stone Gaze.
* Even if she does use Stone Gaze, Nightmare can buy enough time to protect allies and reset the fight.
Additional:
* His Fiend's Grip will leave Medusa defenseless after he's done, if his teammates can provide cover for him or he initiates at the right time by Spell immunity.

* Unlike other illusion heroes, Tempest Double won't be instantly destroyed by Stone Gaze since it is considered a clone and not an illusion.
* 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 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.

* 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.

* Heroes with nukes: Bane, Lich, Lion, Skywrath Mage

* Low-health, normally mobile carries with a lot of damage are vulnerable to Bane's nukes and disables: Anti-Mage, Clinkz, Drow Ranger, Faceless Void, Gyrocopter, Juggernaut, Luna, Meepo, Mirana, Monkey King, Morphling, Phantom Assassin, Phantom Lancer, Riki, Shadow Fiend, Slark, Sniper, Terrorblade, Troll Warlord, Weaver.

* Magnetic Field evades most of Gyrocopter's attacks.
* Necronomicon can kill Gyrocopter with the summons. In addition, Last Will might activate if the Necronomicon Warrior gets killed through Flak Cannon or Call Down.

* 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.

* Low-health, normally mobile carries with a lot of damage are vulnerable to Bane's nukes and disables: Anti-Mage, Clinkz, Drow Ranger, Faceless Void, Gyrocopter, Juggernaut, Luna, Meepo, Mirana, Monkey King, Morphling, Phantom Assassin, Phantom Lancer, Riki, Shadow Fiend, Slark, Sniper, Terrorblade, Troll Warlord, Weaver.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* 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.

* Sonic Wave is a bad choice in abilities if he and the Tempest Double both use Necronomicon and 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.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* Low-health, normally mobile carries with a lot of damage are vulnerable to Bane's nukes and disables: Anti-Mage, Clinkz, Drow Ranger, Faceless Void, Gyrocopter, Juggernaut, Luna, Meepo, Mirana, Monkey King, Morphling, Phantom Assassin, Phantom Lancer, Riki, Shadow Fiend, Slark, Sniper, Terrorblade, Troll Warlord, Weaver.

* Magnetic Field cause attacks from Drow Ranger outside to miss, forcing Drow Ranger to go inside the field, nullifying marksmanship.
Additional:
* 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.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* Arc Warden's Magnetic Field dodges all damage from Death Ward. Should he choose to buy a Necronomicon, they are quite effective to absorb some shots from your cask, and attack you during Death Ward.

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

* Heroes that can disable or silence Silencer for a long time, such as Bane and Legion Commander, can lock down Silencer while their allies put him down.

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

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

* 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.

* Low-health, normally mobile carries with a lot of damage are vulnerable to Bane's nukes and disables: Anti-Mage, Clinkz, Drow Ranger, Faceless Void, Gyrocopter, Juggernaut, Luna, Meepo, Mirana, Monkey King, Morphling, Phantom Assassin, Phantom Lancer, Riki, Shadow Fiend, Slark, Sniper, Terrorblade, Troll Warlord, Weaver.

* 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.

* Low-health, normally mobile carries with a lot of damage are vulnerable to Bane's nukes and disables: Anti-Mage, Clinkz, Drow Ranger, Faceless Void, Gyrocopter, Juggernaut, Luna, Meepo, Mirana, Monkey King, Morphling, Phantom Assassin, Phantom Lancer, Riki, Shadow Fiend, Slark, Sniper, Terrorblade, Troll Warlord, Weaver.

* Bane's Enfeeble makes Ursa more susceptible to disables as it reduces Status Resistance.
* Bane can use Nightmare and Fiend's Grip to lock down Ursa early game and in team fights, forcing Ursa to buy a Black King Bar and making him very vulnerable to being kited once his Black King Bar is down to 5 seconds.
* Overall, Bane's potent disables force Ursa to build more defensive items and play more defensively in general.

* Nightmare and Fiend's Grip can ground Phantom Assassin, who normally blinks around with Phantom Strike, and stop her from outputting damage.
* Phantom Assassin's low health pool early on makes her susceptible to Brain Sap and Fiend's Grip's heavy nuke damage.
Additional:
* Nightmare's lengthy duration prevents Phantom Assassin from finishing off a target enemy hero.
* Fiend's Grip can disable Phantom Assassin, even through spell immunity.

* After Brewmaster has committed Thunder Clap and Cinder Brew to gank, Bane can use Nightmare on Brewmaster to wait out the debuffs, and might even turn the tables by buying time for allied reinforcements.
* Bane can also prevent Brewmaster from using Primal Split with his long disables.

* Enfeeble can be used to decrease Shadow Fiend's already abysmal level one damage even further, preventing him from getting farm and Necromastery stacks.
* Brain Sap allows Bane to heavily harass Shadow Fiend.
* Nightmare allows Bane to set up some early ganks onto Shadow Fiend.
* Fiend's Grip enables Bane to completely take Shadow Fiend out of a fight and potentially even kill him, even through Black King Bar.

* Arc Warden's Flux tears through Refraction charges almost instantly. Should he have a Tempest Double and no creeps are around, a 75% slow means almost certain death.
* Meld is useless against Spark Wraith.
Additional:
* Flux wastes Templar Assassin's Refraction unless she has a Black King Bar or a Manta Style.
* Spark Wraith can be used to bully a Templar Assassin that used Meld.

* Nightmare and Fiend's Grip help to control/disable Troll Warlord in team-fights.

* Brain Sap's magic damage ignores stacks of Reactive Armor.
* Nightmare prevents Timbersaw from using Timber Chain, setting him up for chain stuns and burst damage.
* Fiend's Grip immobilizes Timbersaw and drains his low mana pool, preventing escape afterwards. It also pierces Black King Bar.
* Bane's multiple disables often force Timbersaw or his teammates to spend gold on a Linken's Sphere.

* 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.
Additional:
* 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.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* Fiend's Grip and Nightmare are very useful to lock down Void Spirit.
* Brain Sap can be difficult for Void Spirit to deal with in the laning stage.

* If Bane is outside Chronosphere, he can use Nightmare or Fiend's Grip to cripple Faceless Void inside.
* Nightmare and Fiend's Grip are long duration disables and can render Time Walk's mobility very unreliable.

* Fiend's Grip and an Aghanim's Scepter upgraded Brain Sap pierces spell immunity, rendering Blade Fury nearly useless.

* 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.
* As Necronomicon is his core item, Arc Warden can reveal Mirana and her allies hiding in Moonlight Shadow and the Necronomicon Warrior can kill Mirana with Last Will if he is unintentionally killed with Starstorm upgraded by Aghanim's Scepter or Sacred Arrow.
Additional:
* If Arc Warden builds Necronomicon 3 he can reveal Mirana's team while Moonlight Shadow is active.
* A Starstorm upgraded by Aghanim's Scepter can accidentally kill a Necronomicon Warrior, which can lead to her death if she hasn't built a Black King Bar.
* 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.

* Low-health, normally mobile carries with a lot of damage are vulnerable to Bane's nukes and disables: Anti-Mage, Clinkz, Drow Ranger, Faceless Void, Gyrocopter, Juggernaut, Luna, Meepo, Mirana, Monkey King, Morphling, Phantom Assassin, Phantom Lancer, Riki, Shadow Fiend, Slark, Sniper, Terrorblade, Troll Warlord, Weaver.

* Low-health, normally mobile carries with a lot of damage are vulnerable to Bane's nukes and disables: Anti-Mage, Clinkz, Drow Ranger, Faceless Void, Gyrocopter, Juggernaut, Luna, Meepo, Mirana, Monkey King, Morphling, Phantom Assassin, Phantom Lancer, Riki, Shadow Fiend, Slark, Sniper, Terrorblade, Troll Warlord, Weaver.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

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

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

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

* Heroes with illusions can overwhelm Huskar, as he has no AoE abilities: Phantom Lancer, Anti-Mage, Arc Warden, Chaos Knight.

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

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* Wraith King, Medusa, Storm Spirit and other mana dependent heroes will have diminished impact on a fight if they survive Fiend's Grip due to its mana steal.

* 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 has attack range talent can also outrange Plague Ward.

* Heroes who possess abilities that can save targets from being killed by Reaper's Scythe: Abaddon, Bane, Outworld Devourer, Shadow Demon, Omniknight, etc.

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

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* Low-health, normally mobile carries with a lot of damage are vulnerable to Bane's nukes and disables: Anti-Mage, Clinkz, Drow Ranger, Faceless Void, Gyrocopter, Juggernaut, Luna, Meepo, Mirana, Monkey King, Morphling, Phantom Assassin, Phantom Lancer, Riki, Shadow Fiend, Slark, Sniper, Terrorblade, Troll Warlord, Weaver.

* Heroes with abilities that blind or cause Legion Commander to miss will prevent her from winning Duels: Arc Warden, Keeper of the Light, Riki

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

* Enfeeble, Nightmare and Fiend's Grip all prevent Legion Commander from winning Duels, especially when Bane has Blink Dagger.
Additional:
* Bane has powerful single-target abilities that can help his allies win Duels, or at least cripple Legion Commander for the duration.
* Nightmare can waste Duel's entire duration as the dueled units transfer the Nightmare back and forth. This may be prevented if a non-Dueling unit attacks the Nightmared Dueler.

* Heroes with other kind of disables that pierce spell immunity can hold Pangolier in place during Rolling Thunder: Axe, Beastmaster, Enigma, Magnus, Pudge, Batrider, Bane, Winter Wyvern

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

* 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 Devourer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* Heroes with spell immunity can still be disabled by Fiend's Grip: Juggernaut, Lifestealer, Pangolier.

Additional:
* Fiend's Grip can disable Lifestealer through Rage.

* Low-health, normally mobile carries with a lot of damage are vulnerable to Bane's nukes and disables: Anti-Mage, Clinkz, Drow Ranger, Faceless Void, Gyrocopter, Juggernaut, Luna, Meepo, Mirana, Monkey King, Morphling, Phantom Assassin, Phantom Lancer, Riki, Shadow Fiend, Slark, Sniper, Terrorblade, Troll Warlord, Weaver.

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

* Low-health, normally mobile carries with a lot of damage are vulnerable to Bane's nukes and disables: Anti-Mage, Clinkz, Drow Ranger, Faceless Void, Gyrocopter, Juggernaut, Luna, Meepo, Mirana, Monkey King, Morphling, Phantom Assassin, Phantom Lancer, Riki, Shadow Fiend, Slark, Sniper, Terrorblade, Troll Warlord, Weaver.

* Fiend's Grip's very long disable prevents Anti-Mage from Blinking away or using Manta Style. It also pierces spell immunity.
* Nightmare sets Bane's team up for chain disables on Anti-Mage.
* Enfeeble lowers Anti-Mage's status resistance and magic resistance, making him more vulnerable to disables and magic damage that normally would not affect him much.