* 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.

* 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.

* Any heroes with silences can negate the majority of Outworld Destroyer's damage output: Death Prophet, Night Stalker, Drow Ranger, Doom .

* Heroes who just want to farm and avoid Lone Druid early will find it very hard to do so when he starts knocking on towers: Templar Assassin, Phantom Assassin, Ember Spirit, Morphling.

* 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.

* Heroes with abilities that break Berserker's Blood, lowering Huskar's attack speed and health regeneration: Doom, Shadow Demon, Viper.

* Skywrath Mage also has a terrible time fighting against anything that isn't a hero. His skills are mostly target-based and he has terrible strength and agility, he can easily be kited or harassed by illusion-based heroes like Chaos Knight and Phantom Lancer, or by Heroes that summon other units like Lone Druid, Lycan and Beastmaster.

* 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.

* Heroes who can fight back easily are not ideal matchups for Sven, such as Troll Warlord as mentioned above, Lone Druid and Templar Assassin.

* 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.

* Once caught in Bear's Entangle, Nature's Prophet cannot escape with Teleportation.

* Ember Spirit cannot use his Activate Fire Remnant to escape while affected by Doom.

* Lone Druid becomes unkillable and impenetrable for Ember Spirit on the central line, as it has a huge reserve of health from the Summon Spirit Bear and a large regeneration from Spirit Link, which is why Sleight of Fist practically does not break through either one or the other on the line, and Lone Druid at this time can easily expel Ember Spirit from the line, push and gain gold and level
* Entangling Claws and Savage Roar abilities completely disable Ember Spirit's ability to dodge abilities or get out of an unpleasant fight for him on Fire Remnant, which can give the Lone Druid team the opportunity to kill him
Additional:
* Lone Druid becomes unkillable and impenetrable for Ember Spirit on the central line, as it has a huge reserve of health from the Summon Spirit Bear and a large regeneration from Spirit Link, which is why Sleight of Fist practically does not break through either one or the other on the line, and Lone Druid at this time can easily expel Ember Spirit from the line, push and gain gold and level
* Entangling Claws and Savage Roar abilities completely disable Ember Spirit's ability to dodge abilities or get out of an unpleasant fight for him on Fire Remnant, which can give the Lone Druid team the opportunity to kill him

* 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.

* Lone Druid has a huge reserve of health on the Summon Spirit Bear and a quick regeneration of his health with the help of Spirit Link, which makes Puck's magical abilities almost useless, since they cannot break through such a large pool of health.
* The ability of the Summon Spirit Bear and in the True Form of the Lone Druid, Entangling Claws, allows him to catch Puck when it releases the Illusory Orb, since Puck will not be able to apply Ethereal Jaunt during the root.
Additional:
* Lone Druid has a huge reserve of health on the Summon Spirit Bear and a quick regeneration of his health with the help of Spirit Link, which makes the Puck's magical abilities useless, since they cannot break through such a large pool of health
* The ability of the Summon Spirit Bear and in the True Form of the Lone Druid Entangling Claws allows you to catch Puck when he released the Illusory Orb, since Puck will not be able to apply Ethereal Jaunt during the root action

* 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.

* Lone Druid has a very large reserve of health against Invoker abilities, this allows him to survive a large number of attacks from Invoker and kill him, also Entangling Claws reveal invisibility from Ghost Walk, which allows the Lone Druid team to catch the popular QW-Invoker
Additional:
* Lone Druid has a very large reserve of health against Invoker abilities, this allows him to survive a large number of attacks from Invoker and kill him, also Entangling Claws reveal invisibility from Ghost Walk, which allows the Lone Druid team to catch the popular QW-Invoker

* Doom prevents Storm Spirit from using all of his abilities and items, rendering Storm Spirit useless in a fight.

* True Form gives Lone Druid a huge amount of health that no amount of Ball Lightning will chip through.
* Entangling Claws can mean a very quick end to the Storm Spirit as it prevents him from using Ball Lightning all together.
* Storm Spirit is a single target nuker, with the Shard Lone Druid can always fear him away from himself or the bear, defending the target he does not go on. This is assuming he cannot try and proc his entangle or a potential Skull Basher.

* 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.

* Because of his weak laning phase, Lone Druid absolutely overpowers him in the early to mid game. Lone Druid also directly counters most of his abilities.
* Flux is nullified when the Spirit Bear is nearby.
* Spark Wraith can get soaked by the bear.
* Lone Druid can easily go inside Magnetic Field and punish Zet.

* 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.

* Lone Druid's early game is good against slow, squishy supports since his bear is very strong early game and an Entangling Claws proc almost always guarantees a kill: Ancient Apparition, Crystal Maiden, Shadow Shaman, etc.

* 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.

* Nukers who have set amounts of damage will really struggle against Lone Druid especially in True Form: Puck, Void Spirit, Mars.

* 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

* Heroes who just want to farm and avoid Lone Druid early will find it very hard to do so when he starts knocking on towers: Templar Assassin, Phantom Assassin, Ember Spirit, Morphling.

* Hex abilities prevent attacking, ability and item usage, which is a severe problem for Phantom Assassin as it prevents her from using Black King Bar, the one item that helps protect her against the aforementioned dangers. Doom and Shadow Demon with Aghanim's Scepter also disables Phantom Assassin's Evasion and Critical Strike, removing much of her damage and survivabaility: Doom, Disruptor with Aghanim's Scepter, Dazzle with Aghanim's Shard

* Heroes such as Lone Druid, Tidehunter and Viper can be very problematic for Phantom Assassin because they give her very little time to farm and become scary.

* 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.

* 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 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.

* 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.

* 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.
Additional:
* 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.

* 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.

* 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.
Additional:
* 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.

* 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.

* 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 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 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.

* Alchemist likes to farm fast and be ahead, unfortunately Lone Druid likes to do the same by taking towers.
* Acid Spray will never prove a threat to Lone Druid or his Spirit Bear.
* Chemical Rage may not prove so useful once Lone Druid procs entangled keeping him in place.
* Monkey King Bar is a very good choice on Lone Druid's Spirit Bear and it directly counters any potential Radiance from Alchemist.
* Assault Cuirass is another very good Spirit Bear item that further makes Alchemist vulnerable to physical damage, which is all Lone Druid does.
* Alchemist is not the kind of hero who wants to go on single target summon units, by the time he has killed the Spirit Bear his teammates might had already been slayed by his teammates. Not to mention Lone Druid can just resummon it, even if he is successful.

* 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.

* 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.

* 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.

* Savage Roar interrupts Starbreaker.
* Dawnbreaker is a slow moving hero. Although tanky, Lone Druid can eventually wear her down with his better movement speed.

* Doom makes Ogre Magi less disruptive.
* Infernal Blade effectively negates Ogre Magi's durability.
* With Aghanim's Scepter, he can disable Multicast.

* 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.

* 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.

* Omnislash spreads on both the bear and the druid, allowing them to survive.With enough levels,the bear can soak the ability alone and possibly dragging him to a dangerous location.
* Juggernaut cannot manfight the duo in the early game,because of their tankiness. If opposed in lane,Lone Druid can shut him down.

* 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.

* 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.
Additional:
* 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.

* 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.

* Heroes with silences and hard stuns such as Doom, Silencer, and Lion can keep Mirana from Leaping away.

Additional:
* Doom completely takes Mirana out of a team fight, a hero who relies heavily on using abilities and items to contribute in team fights.

* Heroes that can stop Faceless Void from leaping around the fight and controlling its outcome are very strong against him. Heroes such as: Axe, Centaur Warrunner, Doom...

Additional:
* 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.

* Heroes with silencing abilities can be particularly deadly when Slark is trying to escape: Silencer, Death Prophet, Puck, Doom.

* 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.

* Silencer's Global Silence and Doom's Doom makes Earthshaker temporarily useless.

* Heroes with silences: Puck, Doom, Riki.

* 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.

* 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.

* Chaos Knight, Lone Druid, Meepo and Arc Warden can be hard targets since Shadow Demon's spells are ill-suited to fight many enemies at once.

* Lone Druid's early game is good against slow, squishy supports since his bear is very strong early game and an Entangling Claws proc almost always guarantees a kill: Ancient Apparition, Crystal Maiden, Shadow Shaman, etc.

* Lone Druid's early game is good against slow, squishy supports since his bear is very strong early game and an Entangling Claws proc almost always guarantees a kill: Ancient Apparition, Crystal Maiden, Shadow Shaman, etc.

* 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.

* 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.

* 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.

* 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.

Additional:
* 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.

* 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 makes Ursa less disruptive, and it cannot be dispelled with Enrage upgraded with Aghanim's Scepter.

* Nukers who have set amounts of damage will really struggle against Lone Druid especially in True Form: Puck, Void Spirit, Mars.

* 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.
Additional:
* 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.

* Doom can completely shut down Dazzle through Doom, as it prevents him from casting his abilities and, by extension, gaining Bad Juju stacks.

* Heroes who rely on passive abilities and attacks, such as Drow Ranger, Wraith King, and Lone Druid, can render Silencer useless. But remember that a smart Silencer will most likely buy Silver Edge to counter this if he is played as carry.

Additional:
* Silencer's disables are useless on Lone Druid since he is more reliant on physical attacks rather than spells.
* Silencer has poor mobility so Lone Druid can run him down.
* Lone Druid's Shard will remove most of Silencer's spells once used.

* 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.
Additional:
* 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.