Doom
* Wraith King has three passive abilities and only a single active ability, so Doom does not hinder him significantly.
* Doom expires upon death, so it is effectively removed after 
Reincarnation activates.
Additional:
* Even if he is 
Doomed, Wraith King can tear down Doom with physical attacks, and can still reincarnate as long as it is off-cooldown.
Io
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: 
Beastmaster, 
Broodmother, 
Chaos Knight, 
Lycan, 
Naga Siren, 
Nature's Prophet, 
Phantom Lancer, 
Shadow Shaman, 
Terrorblade, 
Visage, 
Warlock, 
Wraith King.
Doom
* 
Feast deals damage and heals Lifestealer based on the target's maximum HP, which is greatly effective against naturally high HP heroes such as Doom.
* 
Rage allows Lifestealer to become spell immune to negate the magical damage of Infernal Blade and Scorched Earth.
* Doom has no effective means of escape from 
Open Wounds and 
Ghoul Frenzy. This is particularly devastating in the laning stage, where Doom may have to play a much more passive, conservative play style as a result.
Io
* Heroes that can easily bypass Io's allies to get to Io: 
Riki, 
Tusk, 
Clinkz, 
Sniper, 
Slark, 
Phantom Assassin, 
Void Spirit, 
Storm Spirit, 
Ember Spirit, 
Earth Spirit, 
Spirit Breaker, 
Lifestealer.
Doom
* Whenever Doom casts his ultimate, Centaur Warrunner can cast Stampede and allow the Doomed hero to run away, wasting Doom's ultimate.
Additional:
* 
Stampede can be used to free an ally from the grasp of Doom. Without any means of effective lockdown, kills can be difficult to secure when against an enemy Centaur Warrunner. Also, Centaur's tendency to have lots of health and HP regen tend to help counter Doom.
Io
* Heroes that are hard to gank: 
Axe, 
Death Prophet, Phantom Lancer, Slark, 
Centaur Warrunner, 
Bristleback, 
Medusa, 
Mars.
Doom
* Terrorblade can use 
Sunder to save his allies who are Doomed.
Io
* Terrorblade can easily take advantage of Io's weak durability with 
Reflection and 
Metamorphosis.
* As Io relies on boosting his and his 
Tethered target's attack speed with 
Overcharge, Terrorblade can take advantage of this with Reflection, which can damage and slow both, Io and his Tethered target.
* 
Spirits's weak area-of-effect makes it a bad tool to deal with Terrorblade's illusions from 
Conjure Image and 
Manta Style.
* Io's damage output is one of the weakest, therefore Terrorblade will have plenty of time to save himself with Sunder.
* However, Terrorblade has no way of stopping Io to escape with Tether or to stop both, Io and his Tethered target to escape with 
Relocate besides 
Terror Wave from 
Aghanim's Scepter.
Additional:
* Terrorblade can easily take advantage of Io's weak durability with Reflection and Metamorphosis.
* As Io relies on boosting his and his Tethered target's attack speed with Overcharge, Terrorblade can take advantage of this with Reflection, which can damage and slow both, Io and his Tethered target.
* Spirits's weak area-of-effect makes it a bad tool to deal with Terrorblade's illusions from Conjure Image and Manta Style.
* Io's damage output is one of the weakest, therefore Terrorblade will have plenty of time to save himself with Sunder.
* However, Terrorblade has no way of stopping Io to escape with Tether or to stop both, Io and it's Tethered target to escape with Relocate besides Terror Wave from Aghanim's Scepter.
Doom
* Due to the nature of the hero, Sniper is typically situated in the back of the fight, potentially making him a difficult target to initiate on and fight.
* Sniper is largely a right-click hero, and as such isn't as an effective of a Doom target as other heroes.
* Thanks to 
Shrapnel and 
Headshot, Sniper is able to effectively 'kite' Doom, preventing him from closing the distance between the two.
Io
* 
Take Aim and 
Assassinate allow Sniper to reach Io even if it stays in the backline.
Io
* Heroes with high mobility can approach Sniper: 
Anti-Mage, Earth Spirit, 
Io, Nature's Prophet, 
Pangolier, 
Puck, 
Queen of Pain and most notably Riki.
Doom
* Single-target disablers will have difficulty locking down a Chaos Knight with Phantasm active: 
Bane, Beastmaster, 
Bloodseeker, 
Clockwerk, 
Doom, Shadow Shaman.
Io
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: Beastmaster, Broodmother, Chaos Knight, Lycan, Naga Siren, Nature's Prophet, Phantom Lancer, Shadow Shaman, Terrorblade, Visage, Warlock, Wraith King.
Doom
* Heroes who can disable Mars but cannot do any damage to him, meaning he just tanks their abilities: Doom, 
Magnus.
Io
* Heroes that are hard to gank: Axe, Death Prophet, Phantom Lancer, Slark, Centaur Warrunner, Bristleback, Medusa, Mars.
Io
* 
Living Armor and 
Leech Seed can be used to save a hero from a Relocate gank.
* 
Overgrowth can be used to cancel escape attempts with Relocate.
* Once Treant Protector buys Aghanim's Scepter, he will gain access to 
Eyes in the Forest, that will allow him to enchant a tree which will grant him unobstructed vision in that location, allowing him to keep his allies alerted on Io and his Tethered's attempts to gank them, and which can also allow Overgrowth to damage them and root them if they are within a 800 radius of an tree affected by Eyes in the Forest.
Doom
* Doom generally does not impede Sven in almost any way, provided he has activated God's Strength beforehand.
Io
* Lich's 
Chain Frost forces Io to either give up providing buff to his ally with Tether or suffer devastating damage with his Tethered ally.
* Lich can easily use 
Sinister Gaze to disable Io from getting away with Tether or Relocate.
Io
* 
Thirst allows Bloodseeker to see where Io relocated to, should either Io or the tethered hero have low health.
* 
Rupture forces Io to stay in place, preventing it from using the Tether bonus movement speed to escape.
Doom
* The slow applied from 
Corrosive Skin offsets the movement speed bonus granted by Scorched Earth and the tick-based damage from Infernal Blade and Doom will continually slow Doom down. This allows Viper, much like Sniper, to 'kite' Doom and keep him at a safe distance between the two. Additionally, Corrosive Skin applies an attack-speed slow which is fairly crippling to a hero such as Doom that, naturally, has a high base attack-time, poor agility gain and builds little attack-speed items.
* Since Doom does not disable auto-cast abilities, Viper's 
Poison Attack will continue to work. Doom may find it hard to close the distance between himself and Viper, and thusly difficult to effectively lockdown and continually deal damage through his abilities.
Io
* Io is a hero who needs to be close to it's tethered target to make it effective, and that's where Leshrac gets the advantage thanks to many of his area-of-effect abilities.
* 
Lightning Storm will usually hit both Io and its tethered target since both will be close enough for the lightning to jump.
* 
Diabolic Edict and 
Pulse Nova hit all units near Leshrac, meaning he can do colossal damage to both, Io and its tethered target.
Additional:
* Lightning Storm will usually hit both Io and his Tethered target since both will be close enough for the lightning to jump. It can then be followed up by Split Earth.
* Diabolic Edict and Pulse Nova hit all units near Leshrac, meaning he can do colossal damage to Io and his Tethered target.
Io
* Disruptor can always Glimpse back Io or his target after he Relocated nearby.
* Even better, thanks to the indicator on the ground, you can even preemptively drop Static Storm and Kinetic Field on the spot they will relocate to.
* Thunder Strike and Glimpse are also good tools to bring back an Io that Tethered away in the fog of war.
Additional:
* 
Glimpse directly negates Relocate.
* 
Kinetic Field prevents Io from escaping with Tether.
* 
Static Storm can silence and damage both, Io and it's tethered target. And it can also mute both, Io and it's tethered target when upgraded with Aghanim's Scepter.
Io
* Ice Blast prevents Io from healing an ally with Tether and prevents healing from Overcharge
* Io is a common 
Mekansm builder which is useless if he is affected by Ice Blast.
Additional:
* 
Ice Blast prevents Io from healing the target.
* Ancient Apparition can easily harass Io on lane with 
Chilling Touch due to it's high range and damage. This can get even worse if Ancient Apparition buys Aghanim's Scepter and combines it with items that can give him bonus attack damage and attack speed.
* Chilling Touch combined with 
Ice Vortex makes it nearly impossible for Io to escape from 
Cold Feet. Ice Vortex can also make Io and it's tethered target more vulnerable to Ancient Apparition and his allies's magical damage.
Io
* 
Charge of Darkness can be used to escape or counter-initiate against a Relocate gank.
* 
Greater Bash and 
Nether Strike is devastating due to Io's low armor, and can even knock it away from his Tethered target.
Io
* Jakiro's area-of-effect ability arsenal allows him to affect multiple heroes at once, giving Io difficulties in saving them as he can only heal one hero at a time with Tether.
* 
Ice Path can be used to cancel both, Tether and Relocate.
* Jakiro commonly buys 
Rod of Atos that can be used to cancel Relocate, prevent Io in escaping with Tether and make Io easy target for Ice Path and 
Macropyre.
Additional:
* Jakiro's area-of-effect ability arsenal allows him to affect multiple heroes at once, giving Io difficulties in saving them as he can only heal one hero at a time with Tether.
* Ice Path can be used to cancel both, Tether and Relocate.
* Jakiro commonly buys Rod of Atos that can be used to cancel Relocate, prevent Io in escaping with Tether and make Io easy target for Ice Path and Macropyre.
Doom
* Due to Doom's naturally high health, strength gain and common itemization for durability, 
Heartstopper Aura is particularly effective. The health loss is also large enough that, throughout all stages of the game, the aura effectively neuters the health regeneration granted by Devour.
* Necrophos can help to keep both himself and his allies alive during Doom through his natural regeneration granted by Heartstopper Aura (which is not disabled by Doom), or in the case of an ally, through his 
Death Pulse. Additionally, Necrophos is an ideal Mekansm carrier. Should one be bought, kills against Necrophos' team can be difficult to secure due to the damage-over-time nature of Doom and his abilities.
* Doom typically wants to be a hero that soaks attention from the enemy team and takes the role of an initiator and disabler. As such, Doom is an ideal target for 
Reaper's Scythe, as it is likely Doom will be at the fore-front of any fight.
Io
* 
Homing Missile can be used to cancel escape attempts with Relocate.
* 
Flak Cannon allows Gyrocopter to attack both, Io and his Tethered target, especially when upgraded with Aghanim's Scepter.
* 
Rocket Barrage and 
Call Down allow Gyrocopter to deal serious damage to both Io and his Tethered target.
Additional:
* Homing Missile can be used to cancel escape attempts with Relocate.
* Flak Cannon allows Gyrocopter to attack both, Io and his Tethered target, especially when upgraded with Aghanim's Scepter.
* Rocket Barrage and Call Down allow Gyrocopter to deal serious damage to both Io and his Tethered target.
Io
* Soulbind can target both Io and its Tethered ally, allowing Grimstroke and his team to target both with single target spells. Should Io try to Relocate, Phantom's Embrace can stop its channel to prevent escape.
Additional:
* Grimstroke can catch Io and his Tethered ally easily with 
Soulbind as Io has a tendency to Tether himself with an ally frequently, which also makes them easier targets for Soulbind.
* Io is highly vulnerable to disables. Hence, Grimstroke's 
Phantom's Embrace is a great ability to hinder Io's potential.
Io
* 
Ensnare and 
Song of the Siren can be used to cancel both, Tether and Relocate and to close the distance on Io.
* 
Rip Tide combined with illusions from 
Mirror Image often finish off Io before he can save himself with Tether or Relocate.
* Spirits's weak area-of-effect makes it a bad tool to deal with Naga Siren's illusions from Mirror Image.
* Once Naga Siren buys Aghanim's Scepter, she can gain access to 
Reel In, which not only allows her to cancel both, Tether and Relocate, but also to pull Io to herself and her team while he is affected with Ensnare, similarly to Batrider's 
Flaming Lasso.
* 
Aghanim's Shard upgraded Song of the Siren can also heal the hero Io and his Tethered targed try to gank.
Additional:
* Ensnare and Song of the Siren can be used to cancel both, Tether and Relocate and to close the distance on Io.
* Rip Tide combined with illusions from Mirror Image often finish off Io before he can save himself.
* Spirit's weak area-of-effect makes it a bad tool to deal with Naga Siren's illusions from Mirror Image.
* Once Naga Siren buys Aghanim's Scepter, she can gain access to Reel In, which not only allows her to cancel both, Tether and Relocate, but also to pull Io to herself and her team while he is affected with Ensnare, similarly to Batrider's Flaming Lasso.
* Aghanim's Shard upgraded Song of the Siren can also heal the hero Io and his tethered targed try to gank.
Doom
* Phantom Lancer's illusions can make it difficult to Doom the real hero. Should Doom figure out the real hero, the illusions can make it difficult to cast any abilities, as their hitboxes can be used to body-block the real Phantom Lancer.
* Phantom Lancer is an ideal 
Diffusal Blade carrier. With it, he can quite easily deplete Doom's already poor mana pool, potentially making him unable to cast his abilities to escape, retaliate or heal.
* Doom lacks any effective ability to clear waves of creeps and illusions, as the vast majority of his abilities are single-target. Without an answer, Doom may find it difficult to deal with Phantom Lancer's presence.
Io
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: Beastmaster, Broodmother, Chaos Knight, Lycan, Naga Siren, Nature's Prophet, Phantom Lancer, Shadow Shaman, Terrorblade, Visage, Warlock, Wraith King.
Doom
* Doom's Doom marks Phantom Lancer with a highly visible effect, and also silences and mutes him.
* Heroes with undispellable debuffs will help identify the real Phantom Lancer through visual effects or debuff indicators, provided that it was cast on the real Phantom Lancer to begin with:
* Doom's Doom marks Phantom Lancer with a highly visible effect, and also silences and mutes him.
* Bloodseeker's Rupture shows a clear red trail effect on the real Phantom Lancer.
* 
Ancient Apparition's Ice Blast will only debuff Phantom Lancer and not his illusions.
* 
Grimstroke's Soulbind is undispellable.
* 
Shadow Demon's 
Demonic Purge is undispellable.
* 
Monkey King's 
Jingu Mastery is undispellable and puts a big yellow Mark over his head.
Io
* Batrider's Flaming Lasso can be used to cancel Io's attempts to escape with Relocate and drag him away from his Tethered target. And since Io doesn't like buying 
Linken's Sphere, he will be always vulnerable to Batrider's initiations.
* Io's tendency to stick close to it's Tethered target can make Io and it's target vulnerable to Batrider's harrasing.
* Aghanim's Scepter upgraded Flaming Lasso allows Batrider to catch and drag two heroes at once, not just one. Which can potentially turn Io's Tether against him.
Additional:
* Batrider's Flaming Lasso can be used to cancel Io's attempts to escape with Relocate and drag him away from his Tethered target. And since Io doesn't like buying Linken's Sphere, he will be always vulnerable to Batrider's initiations.
* Io's tendency to stick close to it's Tethered target can make Io and it's target vulnerable to Batrider's harrasing.
* Aghanim's Scepter upgraded Flaming Lasso allows Batrider to catch and drag two heroes at once, not just one. Which can potentially turn Io's Tether against him.
Io
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: Beastmaster, Broodmother, Chaos Knight, Lycan, Naga Siren, Nature's Prophet, Phantom Lancer, Shadow Shaman, Terrorblade, Visage, Warlock, Wraith King.
Io
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: Beastmaster, Broodmother, Chaos Knight, Lycan, Naga Siren, Nature's Prophet, Phantom Lancer, Shadow Shaman, Terrorblade, Visage, Warlock, Wraith King.
Io
* Fragile heroes: Bounty Hunter has decent nuking capabilities with Shiruken Toss and Jinada thus making fragile heroes easy picks for ganking. Few examples of such heroes are:
Crystal Maiden, 
Pugna, 
Skywrath Mage, Io, 
Witch Doctor, etc.
Doom
* Heroes with a slow attack rate will find themselves struggling to take out Tombstone, like Doom.
Io
* Heroes with either magical, physical or pure damage burst: Bane, Ember Spirit, 
Leshrac, 
Lina, 
Luna, 
Nyx Assassin, Phantom Assassin, Skywrath Mage, 
Tinker, 
Ursa, Void Spirit.
Io
* Squishy heroes (Io, Crystal Maiden, Lina...), as Earth Spirit can deal tons of damage with Magnetize.
Io
* Heroes with either magical, physical or pure damage burst: Bane, Ember Spirit, Leshrac, Lina, Luna, Nyx Assassin, Phantom Assassin, Skywrath Mage, Tinker, Ursa, Void Spirit.
Doom
* Heroes who often build Linken's Sphere: 
Weaver, 
Morphling, Medusa.
Io
* Heroes whose abilities can affect multiple enemies at once: 
Dawnbreaker, Ember Spirit, Lina, Luna, 
Jakiro, Leshrac, 
Invoker, 
Muerta, 
Dazzle.
Doom
* Heroes with low mana pools (eg.Doom and
Tidehunter) will feel the effects of Silencer's Intelligence Steal far more than others.
Io
* Heroes that can easily bypass Io's allies to get to Io: Riki, Tusk, Clinkz, Sniper, Slark, Phantom Assassin, Void Spirit, Storm Spirit, Ember Spirit, Earth Spirit, Spirit Breaker, Lifestealer.
Io
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: Beastmaster, Broodmother, Chaos Knight, Lycan, Naga Siren, Nature's Prophet, Phantom Lancer, Shadow Shaman, Terrorblade, Visage, Warlock, Wraith King.
Io
* Heroes that can easily bypass Io's allies to get to Io: Riki, Tusk, Clinkz, Sniper, Slark, Phantom Assassin, Void Spirit, Storm Spirit, Ember Spirit, Earth Spirit, Spirit Breaker, Lifestealer.
Io
* Heroes whose abilities can affect multiple enemies at once: Dawnbreaker, Ember Spirit, Lina, Luna, Jakiro, Leshrac, Invoker, Muerta, Dazzle.
Doom
* Heroes who often build Linken's Sphere: Weaver, Morphling, Medusa.
Io
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: Beastmaster, Broodmother, Chaos Knight, Lycan, Naga Siren, Nature's Prophet, Phantom Lancer, Shadow Shaman, Terrorblade, Visage, Warlock, Wraith King.
Io
* 
Cold Embrace can render the extra attack speed from Overcharge meaningless.
* 
Splinter Blast and 
Winter's Curse are very affective against Io, as it has to stay close to his Tethered target.
Doom
* Heroes with the ability to heal allies will not be able to heal heroes affected by Doom: 
Chen, Dazzle, Io, 
Oracle, 
Omniknight, Witch Doctor, 
Winter Wyvern, 
Abaddon, etc.
Doom
* Lone Druid is essentially two heroes. Dooming one over the other still leaves Lone Druid or his bear able to do their job during a fight. Additionally, Lone Druid is not hindered as much as other heroes by the silence and mute of Doom since the hero relies more on attacks than abilities.
Additional:
* Doom will be very hestitant to use Doom on the Spirit Bear, and using it on Lone Druid himself will not stop the bear from attacking him especially if True Form has already been used.
* 
Devour does not work on the Spirit Bear and pushes the lane so Lone Druid can safely farm under tower.
Doom
* Besides 
Lone Druid and 
Meepo, Doom is potentially good versus every hero since Doom will render any hero helpless for up to 16 seconds. This is particularly true for fragile heroes that heavily rely on mobility to stay alive.
Io
* 
Phantom Strike allows Phantom Assassin jump directly to Io.
* 
Coup de Grace can make a short work of Io's low health and armor.
Doom
* Doom with the {ValueColor:1|Doom applies Break|25tal} {Symbol:Talent} talent can be useful against heroes with troublesome passive skills while also disabling them for a long time: Phantom Assassin, 
Enchantress, 
Huskar, 
Underlord.
Io
* 
Lucent Beam can be used to cancel both, Tether and Relocate.
* Like with Leshrac's Diabolic Edict, Lightning Storm and Pulse Nova abilities. Luna's 
Moon Glaives and 
Eclipse abilities can make short work of Io and its tethered ally, particularly when upgraded with Aghanim's Scepter.
Additional:
* Lucent Beam and 0.25s Eclipse Lucent Ministun talent for Eclipse can be used to cancel both, Tether and Relocate.
* Luna's Moon Glaives and Eclipse abilities can make short work of Io and its tethered ally, particularly when upgraded with Aghanim's Scepter.
Doom
* Heroes that can keep Luna locked down for a long time can be a threat (she is very item and spell dependent): 
Faceless Void, 
Legion Commander, Doom.
Doom
* High health heroes (Axe, Doom) fall fast with Fury Swipes stacks.
Io
* Heroes with either magical, physical or pure damage burst: Bane, Ember Spirit, Leshrac, Lina, Luna, Nyx Assassin, Phantom Assassin, Skywrath Mage, Tinker, Ursa, Void Spirit.
Doom
* Doom makes Ursa less disruptive, and it cannot be dispelled with Enrage upgraded with Aghanim's Scepter.
Doom
* 
Infernal Blade deals high damage to Pudge due to his scaling health and strength gain from 
Flesh Heap.
* Using Doom with timing against Pudge who had just activated 
Rot would usually kill him.
Additional:
* Doom disables the toggling of Rot and, if cast at the right time, may leave Pudge with a potentially lethal health drain.
* Doom's naturally high health, strength gain and damage output makes him a poor target for Pudge.
* The damage of Doom's Infernal Blade scales with the target's maximum health, which is particularly effective against Pudge due to his naturally high health and further health granted by stacks of Flesh Heap.
Io
* Tether and Overcharge makes it much harder for Pudge to kill a target with 
Meat Hook, and Relocate can save the Io's ally while 
Dismember is being channeled.
Doom
* Besides Lone Druid and Meepo, Doom is potentially good versus every hero since Doom will render any hero helpless for up to 16 seconds. This is particularly true for fragile heroes that heavily rely on mobility to stay alive.
Io
* Tether helps Io escape from Earthbind even if Meepo has Blink Dagger.
* Io's Spirits can pressure Meepo while laning and will usually hit at least one of his clones.
Io
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: Beastmaster, Broodmother, Chaos Knight, Lycan, Naga Siren, Nature's Prophet, Phantom Lancer, Shadow Shaman, Terrorblade, Visage, Warlock, Wraith King.
Doom
* Doom can eats Nature's Prophet's treants with Devour and gains lots of gold.
* Doom can buy 
Radiance or use his 
Scorched Earth to quickly wipe out a swarm of Treants.
* Doom and a ministun from Infernal Blade's prevents Nature's Prophet from escaping with Sprout and Teleportation.
Io
* Nature's Prophet is extremely easy to gank with Relocate while he's split pushing.
* Tether on a friendly unit can destroy Nature Prophet's trees should he surround himself with 
Sprout as a defense.
Doom
* Doom can easily kill Chen's creeps and obtain their abilities with Devour.
* Scorched Earth's area-of-effect can clear multiple of Chen's creeps at once.
* Doom renders Chen completely helpless, and unable to save himself or his allies with 
Hand of God. Aghanim's Scepter upgraded Doom also allows Doom to cast Doom on himself and disable both, Chen and his creeps around him.
Doom
* Doom completely takes Mirana out of a team fight, a hero who relies heavily on using abilities and items to contribute in team fights.
Doom
* Doom is generally tanky and has naturally high health, allowing him to survive Puck's onslaught in any stage of the game.
* His namesake ultimate Doom is one of the best solutions to counter Puck, as it will silence Puck for a lengthy duration. A Puck silenced for more than 3 seconds usually ends up dead.
* In addition, if Doom chooses the Level 25 talent Doom applies Mute, Puck will not be able to use items altogether, most especially 
Blink Dagger and 
Eul's Scepter of Divinity, making Doom a nightmare to deal with as Puck.
Doom
* Infernal Blade's damage is calculated by percentage of maximum health. Since Spectre is usually tanky, it will hurt her more than most normal attacks.
* Doom can take out Spectre out of a teamfight completely. When combined with the level 25 talent {ValueColor:1|Doom applies Break|25tal} {Symbol:Talent}, it will disable both 
Desolate and 
Dispersion, taking away her extra damage and durability.
Additional:
* Infernal Blade's damage is calculated by percentage of maximum health, meaning that it will hurt Spectre more than most normal attacks, negating some of her tankiness.
* Doom can pick up several different abilities from neutral creeps using Devour, some of which can be annoying to Spectre.
* Mud Golem, Dark Troll Summoner, Harpy Stormcrafter, Satyr Mindstealer or Satyr Tormenter are good examples.
* Doom makes Spectre less disruptive. Combined with Aghanim's Scepter, it will disable Spectre passive skills, reducing her potential in teamfights.
Doom
* Doom alone can easily pick off Crystal Maiden since she is fairly fragile, even with using only basic attacks, Infernal Blade, and Scorched Earth.
* Doom prevents her from using any abilities in a fight, making her impact negligible.
* Devour allows Doom to acquire a stun, allowing him to cancel Freezing Field without having to use Doom.
Doom
* Doom shuts down Anti-Mage's escape capabilities with Blink. The ability also deals pure damage, which ignores the protection from Counterspell.
* However, a well-timed Counterspell can reflect it back.
* If Doom has Aghanim's Scepter, Doom can break Mana Break and Counterspell, weakening both his offense and defense.
* Doom's low mana pool causes him to take little damage from Mana Void.
Additional:
* Doom prevents Anti-Mage from maneuvering around a fight or escaping from an initiation using 
Blink. Additionally, Doom deals pure damage, which is not affected by 
Counterspell. This can quickly whittle away Anti-Mage's naturally poor health pool.
* However, Doom must be careful when using Doom as a well-timed Counterspell can block and reflect it back against Doom himself.
* The Level 25 talent {ValueColor:1|Doom applies Break|25tal} {Symbol:Talent} will also disable 
Mana Break and Counterspell's passive component, which makes Anti-Mage significantly less effective in fights and more susceptible to the high magical damage of Doom's abilities and his allies.
Doom
* Faceless Void relies on 
Time Walk for mobility and survivability but he can be prevented from utilizing it through Doom.
* Doom has a high cooldown duration for every ability except Infernal Blade, so he is not significantly affected by 
Time Dilation.
Doom
* Infernal Blade deals scaling damage and is useful against high HP targets such as Timbersaw.
* Timbersaw is extremely reliant on his abilities to be effective during a team fight - both for mobility, damage and crowd control. Timbersaw offers very little, impactful right-click damage, and thus Doom is particularly crippling against him.
* Additionally, when Doom chooses the {ValueColor:1|Doom applies Break|25tal} {Symbol:Talent} talent, Doom disables 
Reactive Armor, which effectively removes the durability which Timbersaw is commonly known for.
Additional:
* Doom shuts down Timbersaw completely, negating his mobility and preventing him from doing any damage. It also breaks Reactive Armor's passive bonuses from Aghanim's Scepter.
* Infernal Blade can stun Timbersaw several times in a fight, potentially interrupting Timber Chain. Also it's useful since Timbersaw has high HP due to the damage scales based on max HP.
Doom
* Doom has several disable abilities to choose from jungle creeps (e.g. 
War Stomp, 
Ensnare) to deal with Shadow Fiend who lacks escape abilities.
* When Doom combines creep abilities with Scorched Earth, Infernal Blade, and Doom, Shadow Fiend most likely will die as he cannot use Shadowraze and Requiem of Souls to protect himself, and also cannot even flee by using 
Shadow Blade or Blink Dagger.
* Although Shadow Fiend has a high physical damage output, Doom has a large health pool to survive it, meaning Doom's combo with high magical damage output will shutdown Shadow Fiend first.
* Doom usually buys Radiance to improve his damage, making his nuke combo more deadly to Shadow Fiend. The blind also prevents Shadow Fiend from landing his attacks often.
Doom
* Infernal Blade deals scaling damage and is useful against high HP targets such as Tidehunter.
* Doom prevents Tidehunter from casting his 
Gush, 
Anchor Smash and 
Ravage, making him useless in team fights.
* If Doom chooses the Level 25 talent {ValueColor:1|Doom applies Break|25tal} {Symbol:Talent}, he can also disable 
Kraken Shell, reducing his survivability.
Io
* Phoenix's limit AoE, damage-over-time abilities give Io plenty of time to save allies with Relocate.
Doom
* Doom completely takes Windranger out of a team fight, a hero who relies heavily on using abilities and items to contribute in team fights.
Additional:
* Doom completely takes Windranger out of a team fight, a hero who relies heavily on using abilities and items to contribute in team fights.
Doom
* Doom pierces spell immunity and can prevent Enigma from casting any spells or using items until the duration of the spell depletes, as well as cancelling a 
Black Hole.
* While Doom can be blocked by a Linken's Sphere, which is a common item on Enigma, Aghanim's Scepter upgraded Doom allows Doom to cast Doom on himself to affect enemies near him, and if Doom can combine this with Blink Dagger, he will be able to jump on Enigma while he is channeling Black Hole. Aghanim's Scepter upgraded Doom can also cancel Black Hole if any of Enigma's allies affected by Doom gets too close to him for it's duration, ignoring both, 
Black King Bar and Linken's Sphere.
Doom
* Infernal Blade deals scaling damage and is useful against high HP targets such as Elder Titan. It also can interrupt 
Echo Stomp if quick enough.
* Doom has very low base armor and naturally high HP, so he isn't significantly affected by 
Natural Order.
Doom
* 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.
Doom
* Doom with the {ValueColor:1|Doom applies Break|25tal} {Symbol:Talent} talent can be useful against heroes with troublesome passive skills while also disabling them for a long time: Phantom Assassin, Enchantress, Huskar, Underlord.
Additional:
* Infernal Blade does damage based on percentage health, and is useful against high health pool hero like Underlord.
* Doom can prevent Underlord from spamming his abilities and most important is to prevent him from using Fiend's Gate to escape.
Io
* Io can escape from Pit of Malice with Tether or Relocate.
* Relocate can counter Dark Rift's split pushing.
Doom
* Arc Warden relies on items and abilities, as well as his 
Tempest Double, to deal damage to enemies. Doom effectively denies that and makes Arc Warden useless in fights.
Doom
* Doom applies a basic dispel upon cast, so it can remove 
Guardian Angel.
* Casting Doom on Omniknight will also prevent him from healing allies with 
Purification, or casting buffs like 
Repel and Guardian Angel, basically turning him into a harmless creep.
Additional:
* Doom turns Omniknight into a walking creep, or completely takes out his buffed cores, also removing Heavenly Grace and Guardian Angel in the process.
* With Devour used on Satyr Banisher, Doom will have access to Satyr Banisher's 
Purge, which will allow him to remove Heavenly Grace and Guardian Angel.
Doom
* Doom will make Abaddon unable to use Mist Coil, Aphotic Shield, and the active component of Borrowed Time, also upgraded with Aghanim's Scepter can break Curse of Avernus and the passive component of Borrowed Time ,which means his allies could be easily disabled or killed.
Doom
* Doom with the {ValueColor:1|Doom applies Break|25tal} {Symbol:Talent} talent can be useful against heroes with troublesome passive skills while also disabling them for a long time: Phantom Assassin, Enchantress, Huskar, Underlord.
Additional:
* Devour can easily eat creeps controlled by Enchant, limiting her ganking potential.
* Doom reduces the amount of healing received by Enchantress and her allies from Nature's Attendants. In addition, when Doom chooses the Doom applies Break talent, it can also disable Untouchable.
Doom
* Weak damage but high tick rate or persist in a long time: Slark, 
Gyrocopter, Queen of Pain, Shadow Shaman (
Shackles), Jakiro, Pugna, Doom
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, 
Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna, Doom
Doom
* Doom with the {ValueColor:1|Doom applies Break|25tal} {Symbol:Talent} talent can be useful against heroes with troublesome passive skills while also disabling them for a long time: Phantom Assassin, Enchantress, Huskar, Underlord.
Doom
* Heroes with silences: Puck, Doom, Riki.
Doom
* Heroes with the ability to heal allies will not be able to heal heroes affected by Doom: Chen, Dazzle, Io, Oracle, Omniknight, Witch Doctor, Winter Wyvern, Abaddon, etc.
Io
* Heroes with abilities that can save teammates are also effective such as Shadow Demon, Dazzle, Oracle, Bane, Pugna, Tusk, Winter Wyvern, Io, Underlord, 
Treant Protector and 
Keeper of the Light.
Doom
* 
Silencer's 
Global Silence and Doom's Doom makes Earthshaker temporarily useless.
Doom
* Heroes with the ability to heal allies will not be able to heal heroes affected by Doom: Chen, Dazzle, Io, Oracle, Omniknight, Witch Doctor, Winter Wyvern, Abaddon, etc.
Io
* Heroes whose abilities can affect multiple enemies at once: Dawnbreaker, Ember Spirit, Lina, Luna, Jakiro, Leshrac, Invoker, Muerta, Dazzle.
Doom
* Doom completely takes Invoker out of a team fight, a hero who relies heavily on using abilities and items to contribute in team fights.
Additional:
* Doom is a good way to shut down Invoker, preventing from casting spells and using items for a lengthy time, thus forcing him to invest on Linken's Sphere.
Io
* Heroes that can easily bypass Io's allies to get to Io: Riki, Tusk, Clinkz, Sniper, Slark, Phantom Assassin, Void Spirit, Storm Spirit, Ember Spirit, Earth Spirit, Spirit Breaker, Lifestealer.
Doom
* Doom prevents Storm Spirit from using all of his abilities and items, rendering Storm Spirit useless in a fight.
Io
* Heroes with either magical, physical or pure damage burst: Bane, Ember Spirit, Leshrac, Lina, Luna, Nyx Assassin, Phantom Assassin, Skywrath Mage, Tinker, Ursa, Void Spirit.
Doom
* A well-timed Doom prevents Nyx Assassin escaping with Vendetta and fighting back with 
Spiked Carapace.
* Doom's high health also allows him to easily shrug off Nyx Assassin's burst damage and fend him off.
Io
* Heroes that are hard to gank: Axe, Death Prophet, Phantom Lancer, Slark, Centaur Warrunner, Bristleback, Medusa, Mars.
Doom
* Doom can stop Death Prophet from casting spells, which makes her useless during team fights if she didn't cast Exorcism before the fight, and also nullifies healing from Exorcism and Spirit Syphon. Furthermore, Doom can use Scorched Earth to chase after her.
Io
* Heroes with either magical, physical or pure damage burst: Bane, Ember Spirit, Leshrac, Lina, Luna, Nyx Assassin, Phantom Assassin, Skywrath Mage, Tinker, Ursa, Void Spirit.
Doom
* Doom is effective against every hero, and Void Spirit is no exception. Being unable to cast spells or items during fights for 16 seconds nullifies his impact entirely.
* Doom has a very versatile build and can consume creeps which has abilities that can stun or provide additional magic resistance.
* Doom's high strength gain and versatility in items can be effective against Void Spirit's magical damage.
Io
* Heroes with either magical, physical or pure damage burst: Bane, Ember Spirit, Leshrac, Lina, Luna, Nyx Assassin, Phantom Assassin, Skywrath Mage, Tinker, Ursa, Void Spirit.
Doom
* Both Infernal Blade and Doom can be used to disable Bane while he is channeling Fiend's Grip.
* A similar effect can be achieved by using Devour on {U:Centaur Conqueror}, which will give him access to War Stomp.
Io
* Heroes with either magical, physical or pure damage burst: Bane, Ember Spirit, Leshrac, Lina, Luna, Nyx Assassin, Phantom Assassin, Skywrath Mage, Tinker, Ursa, Void Spirit.
Doom
* Ember Spirit cannot use his 
Activate Fire Remnant to escape while affected by Doom.
Io
* Heroes that are hard to gank: Axe, Death Prophet, Phantom Lancer, Slark, Centaur Warrunner, Bristleback, Medusa, Mars.
Doom
* Infernal Blade's damage is calculated by a percentage of maximum health, meaning that it will hurt Axe more than most normal attacks, negating some of his durability.
* Doom can pick up several different abilities from neutral creeps using Devour, some of which can be annoying to Axe.
* Mud Golem, Dark Troll Summoner, Harpy Stormcrafter, Satyr Mindstealer or Satyr Tormenter are good examples.
* Doom's naturally low attack speed makes Counter Helix less likely to proc, and his high base health allows him to take a few Helixes with no danger.
* Doom makes Axe less disruptive, preventing him from using his skills or items. At level 25, there is a branch of the talent tree that makes Doom apply Break, allowing Doom to disable Counter Helix, making Axe effectively useless for a lengthy duration.
Additional:
* Infernal Blade deals scaling damage and is useful against high HP targets such as Axe.
* Doom has low attack speed because of his high Base-Attack-Time, poor agility gain and limited attack-speed granting items which are commonly built. This means Doom will trigger 
Counter Helix less often and thus is an unideal target for initiation.
* Doom has naturally high HP so it takes longer for Doom to be brought down to the killing threshold of 
Culling Blade.
* Axe is highly reliant on his abilities and items to be effective during a fight. Without the usage of 
Berserker's Call and Blink Dagger due to Doom, Axe offers very little in the way of damage, effectively removing him from a fight.
Io
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: Beastmaster, Broodmother, Chaos Knight, Lycan, Naga Siren, Nature's Prophet, Phantom Lancer, Shadow Shaman, Terrorblade, Visage, Warlock, Wraith King.
Doom
* Scorched Earth can be used to engage Visage while removing Gravekeeper's Cloak charges.
* Infernal Blade will deal tremendous amounts of damage over time due to Visage's high health pool.
* Doom completely nullifies Gravekeeper's Cloak and prevents Visage from casting spells.
Io
* Heroes with either magical, physical or pure damage burst: Bane, Ember Spirit, Leshrac, Lina, Luna, Nyx Assassin, Phantom Assassin, Skywrath Mage, Tinker, Ursa, Void Spirit.
Doom
* Tinker is heavily dependent on his abilities and Doom prevents him from using any of them.
* This becomes even worse if Doom chooses the level 25 talent {ValueColor:1|Doom applies Mute|25tal} {Symbol:Talent}, which will prevent Tinker from using items such as Blink Dagger.
Additional:
* Tinker is heavily reliant on casting his spells and Doom can disable all of his abilities and items. An Aghanim's Scepter only makes it harder for Tinker to survive.
Io
* 
Quill Spray is very effective against Io, as it has very low armor and has to stay close to the fight to not break its Tether.
Doom
* Infernal Blade deals scaling damage and is useful against high health targets such as Bristleback.
* Doom disables Bristleback's low cooldown abilities, preventing him from triggering Warpath. With his upgraded level 25 talent, it also breaks Bristleback's passive, rendering him more vulnerable.
Additional:
* Infernal Blade deals scaling damage and is useful against high HP targets such as Bristleback.
* Doom prevents Bristleback from casting his two low cooldown abilities, which then prevents him from utilizing 
Warpath.
* If Doom chooses the Level 25 talent {ValueColor:1|Doom applies Break|25tal} {Symbol:Talent}, he can disable 
Bristleback and Warpath, taking away much of his durability and damage potential in team fights.
Io
* 
Poison Touch allows Dazzle to harass both, Io and it's tethered target on lane. Aghanim's Shard upgraded Poison Touch can also hex both, Io and it's tethered target, preventing them from escaping with Relocate, and also disarming them, silencing them, muting them and rendering them helpless against Dazzle and his allies.
* Io's damage output is one of the weakest, therefore Dazzle will have plenty of time to save an ally with 
Shallow Grave from gank by Io and it's tethered target.
* 
Shadow Wave will always hit both, Io and it's tethered target if they are near the ally Dazzle uses Shadow Wave on, while healing Dazzle's allies near them. Aghanim's Scepter upgraded Shadow Wave can bounce on both, Io and it's tethered target, causing them both to take damage and to be attacked by Dazzle. And unlike Io who doesn't get healed while using Tether, Shadow Wave will always heal Dazzle no matter on which of his allies he uses it on.
* 
Bad Juju will cause both, Io and it's tethered target to lose armor every time Dazzle casts a spell while strengthening armor of Dazzle's allies.
Additional:
* Poison Touch allows Dazzle to harass both, Io and it's Tethered target on lane. Aghanim's Shard upgraded Poison Touch can also hex both, Io and it's Tethered target, preventing them from escaping with Relocate, and also disarming them, silencing them, muting them and rendering them helpless against Dazzle and his allies.
* Io's damage output is one of the weakest, therefore Dazzle will have plenty of time to save an ally with Shallow Grave from gank by Io and it's Tethered target.
* Shadow Wave will always hit both, Io and it's Tethered target if they are near the ally Dazzle uses Shadow Wave on, while healing Dazzle's allies near them. Aghanim's Scepter upgraded Shadow Wave allows Dazzle Shadow Wave directly on Io and it's Tethered target which can also bounce on both, Io and it's tethered target, causing them both to take damage and to be attacked by Dazzle. And unlike Io who doesn't get healed while using Tether, Shadow Wave will always heal Dazzle no matter on which of his allies he uses it on.
* Bad Juju will cause both, Io and it's tethered target to lose armor every time Dazzle casts a spell while strengthening armor of Dazzle's allies.
Doom
* Doom can completely shut down Dazzle through Doom, as it prevents him from casting his abilities and, by extension, gaining Bad Juju stacks.
Io
* Heroes that can easily bypass Io's allies to get to Io: Riki, Tusk, Clinkz, Sniper, Slark, Phantom Assassin, Void Spirit, Storm Spirit, Ember Spirit, Earth Spirit, Spirit Breaker, Lifestealer.
Doom
* Heroes with silencing abilities can be particularly deadly when Slark is trying to escape: Silencer, Death Prophet, Puck, Doom.
Doom
* Drow Ranger can be difficult to get on top of, thanks to her 
Frost Arrows and 
Gust. With these two abilities, Drow Ranger is able to effectively 'kite' Doom and minimize his impact during team fights and laning stage.
* Much of Drow Ranger's effectiveness comes from her passive 
Marksmanship, which is not disabled by Doom.
Io
* Drow Ranger's lack of escape abilities makes her an easy target for Relocate ganks.
Doom
* Doom's low armor makes him weak against Alchemist's high physical damage output.
Doom
* Doom can disable 
Chemical Rage's increased healing, rendering Alchemist helpless against Doom.
* Attacks from Infernal Blade can deal serious damage to Alchemist as it deals damage based on the hero's maximum health.
Io
* Fireblast is a good tool to interrupt Io during its escapes through Tether.
* Ignite can be one of the few spells with enough total damage to out-trade the sustained healing Io provides for its fellow laner.
* However, picking other supports that focus less on the laning phase is generally a better choice against Io.
Doom
* Doom makes Ogre Magi less disruptive.
* Infernal Blade effectively negates Ogre Magi's durability.
* With Aghanim's Scepter, he can disable Multicast.
Io
* Heroes with both illusions and summons, for Io has nothing to deal with multiple enemies at once outside from Spirits's weak area-of-effect: Beastmaster, Broodmother, Chaos Knight, Lycan, Naga Siren, Nature's Prophet, Phantom Lancer, Shadow Shaman, Terrorblade, Visage, Warlock, Wraith King.
Doom
* Supports with useful teamfight or contribution spells will be helpless against Doom: Dazzle, Oracle, Warlock.
Additional:
* Doom will not only prevent Warlock from casting his abilities in team fights, but also it reduces the healing from Shadow Word.
* Devour allows Doom to acquire a stun from neutral creeps, allowing him to interrupt Upheaval without having to use Doom.
Io
* 
Strafe, 
Tar Bomb and 
Burning Barrage from Aghanim's Shard allow Clinkz to quickly kill Io due to its low armor.
* Clinkz iz a hero that very often goes for 
Orchid Malevolence, and its upgrade 
Bloodthorn. Alternatively, Clinkz also loves to buy 
Gleipnir. And if Clinkz has both of them, he will be able to root and silence Io and prevent him from escaping with either Tether or Relocate.
Doom
* Scorched Earth deals damage to Clinkz during Skeleton Walk.
* Doom shuts down Clinkz entirely, as it prevents him from casting any of his spells and contributing a large amount of damage in teamfights.
Doom
* Any heroes with low mana pools will die quickly or even instantly to Sanity's Eclipse: Doom, Phantom Assassin, 
Troll Warlord.
Doom
* Any heroes with silences can negate the majority of Outworld Destroyer's damage output: Death Prophet, 
Night Stalker, 
Drow Ranger, Doom .
Io
* 
Duel is very effective against Io due to its low health and armor.
Io
* Tethered heroes are much harder for Legion Commander to kill in Duels.
* Relocate can cancel Duels and save allies.
Doom
* Doom does not disable
Mana Shield. As such, Doom's damage is largely mitigated by her mana shield. Additionally, Medusa is not reliant on her abilities to be effective during a teamfight, making Medusa an unproductive hero to target. 
Linken's Sphere carrier. Should one be purchased, and without any additional disables, Doom may find that few opportunities exist to effectively lockdown, disable, and kill Medusa.
* Medusa is an ideal
Io
* Heroes that are hard to gank:
Axe, 
Death Prophet, 
Phantom Lancer, 
Slark, 
Centaur Warrunner, 
Bristleback, 
Medusa, 
Mars.