* 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.

* Disruption can banish Faceless Void or an ally in Chronosphere, making it a less effective ability.
* Faceless Void's illusions created by Disruption will not get stunned by Chronosphere, allowing Shadow Demon to attack Faceless Void in his Chronosphere.
* Casting Disruption after releasing Shadow Poison charges will make Time Walk unable to backtrack the damage.
* Shadow Poison is a good way to deal damage as the initial damage and the release damage can't both be Time Walked at the same time.
* Demonic Purge is a great slow, useful to force out a Time Walk early and can break Time Lock with Aghanim's Scepter.

* Infernal Blade's damage is calculated by 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 effectevely 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.

* Disruption will save Shadow Demon's teammates from being killed by Counter Helix or Culling Blade.
* Demonic Purge slows Axe to a crawl, making him nearly useless after initiating. If Shadow Demon has Aghanim's Scepter, it will also break Counter Helix.
* Demonic Cleanse clears Battle Hunger and Aghanim's Shard Counter Helix Damage Reduction, both allowing targets to escape, and reducing your own survivability.
Additional:
* While it is unwise to encounter Axe alone, Disruption can be used to save your allies from Axe's initiate Berserker's Call, or, if timed correctly, from his Culling Blade.
* Illusions spawned from Axe has the Counter Helix passive, which with deal some nasty damage if an enemy focuses them
* Your upgraded Demonic Purge breaks Axe's primary damage output: Counter Helix, This can be used on him during Berserker's Call to seriously hinder him.
* Demonic Cleanse will clear Battle Hunger, which is Axe's method of catching heroes, and Shard upgraded Counter Helix's Damage Reduction, which is one of Axe's primary survivability abilities.

* Infernal Blade's damage is calculated by percentage of max health. Since Spectre is usually tanky, it will hurt her more than most normal attacks.
* Doom can entirely disable Spectre from a teamfight. If upgraded with Aghanim's Scepter, it will disable her passive skills which is she relies on, crippling her.
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.

* Her illusions with Desolate are very valuable, especially when they are usually paired with Radiance. Unlike blink or force movement, Spectral Dagger's escaping mechanic requires manual movement, and therefore Demonic Purge can hold her back really hard and allow your allies to finish her off.
* If she tries to kill you or any key ally with Haunt at any point of the game, remember to not panic and always use Disruption on the illusion, whether it is fake or the real Spectre herself. When the situation calls, Demonic Purge can save a second victim from a haunting Spectre.
* When upgraded by Aghanim's Scepter, Demonic Purge can remove Spectre from a fight by disabling Desolate and Dispersion, negating her damage and tankiness respectively.

* 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.
* Be careful when using Doom as a well-timed Counterspell can block and reflect it back against Doom himself.
* An Aghanim's Scepter upgraded Doom will also disable Mana Break and Counterspell, which makes Anti-Mage significantly less effective in fights and more susceptible to the high magical damage of Doom's abilities and his allies.

* Disruption sets up Anti-Mage for a chain disable. The illusions will deal extra damage due to Mana Break.
* Shadow Poison hits Anti-Mage even after he's Blinked away.
* If Shadow Demon has Aghanim's Scepter, Demonic Purge can break Mana Break and Counterspell, weakening both his offense and defense.
Additional:
* While it is unwise to encounter Anti-Mage alone, Disruption's considerable cast range can become a perfect setup for any hard-disable to follow up. If he is pinned down, Anti-Mage will quickly face his demise when the illusions deplete his already low mana pool. Manta Style will easily allow him to escape, however.
* The illusions can be controlled to quickly sap mana from any other target, making Anti-Mage one of the most valuable targets to disrupt.

* 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 gets an Aghanim's Scepter, he can disable Bristleback and Warpath, taking away much of his durability and damage potential in team fights.

* Shadow Demon's Demonic Purge with Aghanim's Scepter disables Bristleback's passives.

* 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.

* Heroes with high physical damage output but lack of reliable escape mechanisms are always a good target for a solo gank: Sniper, Shadow Fiend, Troll Warlord, Drow Ranger. Those heroes, however, are dangerous if they manage to close the gap, so take caution.

* An Aghanim's Scepter upgraded Doom can be useful against heroes with troublesome passive skills while also disabling them for a long time: Phantom Assassin, Enchantress, Huskar, Underlord.

* Shadow Demon's Shadow Poison can quickly stack to the point where Huskars generally low health is easily finished off.
* Shadow Demon's Disruption can turn Huskar's high attack speed and regeneration against him, It also makes him an easy target for Shadow Poison,
* Shadow Demon commonly builds a Meteor Hammer, allowing him to land a heavy stun on Huskar
* Shadow Demon's upgraded Demonic Purge breaks Huskar, It also pierces Spell Immunity, Without his passive for 7 seconds Huskar quickly falls in battle
* However note that Shadow Demon is a squishy target and you can often overwhelm him if he is alone, But he can still Disrupt you to escape
Additional:
* Shadow Poison can quickly stack up on Huskar, And with his naturally low health you don't need as many stacks to be effective.
* Disruption turns Huskars high attack speed against him, They also have the highest survivability as illusions due to his passive Berserker's Blood, It also allows you to put Shadow Poison stacks on him,
* Dissimulate turns Huskar's burning damage against his team, You can cast it on an ally who is taking a bunch of Burning Spear stacks and cause Huskar to take high amounts of damage as well
* Scepter upgraded Demonic Purge is your most effective weapon against him, It's 7 second Break causes him to quickly die in battle

* Tinker is heavily dependent on active abilities and Doom prevents him from using any of them.
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.

* Heroes that can gain vision over trees to catch Tinker: Invoker, Shadow Demon, Batrider.

* An Aghanim's Scepter upgraded Doom can be useful against heroes with troublesome passive skills while also disabling them for a long time: Phantom Assassin, Enchantress, Huskar, Underlord.

* Heroes with break can disable Untouchable for a while: Doom and Shadow Demon (via Aghanim's Scepter), Viper, Shadow Shaman with Hex Breaks talent.

* An Aghanim's Scepter upgraded Doom can be useful against heroes with troublesome passive skills while also disabling them for a long time: Phantom Assassin, Enchantress, Huskar, Underlord.

* Doom, Disruptor with Aghanim's Scepter, and hex abilities all prevent 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.

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

* Heroes with summons or illusions makes Sacred Arrow harder to land: Shadow Demon, Phantom Lancer, Nature's Prophet.

* Disruption instantly removes Phantom Embrace, and can potentially save allies affected by Soulbind.
* Demonic Purge dispels Ink Swell.

* 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 this hero.
* Additionally, when upgraded with Aghanim's Scepter, Doom breaks 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 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.

* 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.

* 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.

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

* Shadow Demon's spammable illusions can be used to scout Techies' Proximity Mines. The illusion of your carries can be even used to trick Techies into detonating his precious Remote Mines.

* 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 gets an Aghanim's Scepter, he can also disable Kraken Shell, reducing his survivability.

* Shadow Demon can waste precious seconds of Windrun with Disruption.
* Alternatively, Demonic Purge can be used to dispel it altogether, leaving her completely defenseless for 7 seconds.
* Disruption can be used to save an ally if they get stunned by Shackleshot.
Additional:
* Shadow Demon can waste precious seconds of Windrun with Disruption.
* Alternatively, Demonic Purge. can be used to dispel it altogether, leaving her completely defenseless.
* Disruption can be used to save an ally if they get stunned by Shackleshot.

* 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.

* Infernal Blade deals high damage to Pudge due to his high strength grow with 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.

* 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.

* Demonic Purge takes off Luna's superior mobility, removing the need for chasing her and allowing your team to reposition in team fights or escape when at low HP. If Shadow Demon has Aghanim's Sceptre it will also take away glaive bounces and extra damage from Luna's passive.
* Luna's illusions created by Disruption are very valuable with their Moon Glaives. These will effectively counter her pushing attempts and are painfully effective in team fights.
* Disruption can be used to save an ally from Eclipse.
* For the same reasons, Shadow Demon makes a very powerful ally for Luna when they are in the same team.
Additional:
* Demonic Purge takes off Luna's superior mobility, removing the need for chasing her and allowing your team to reposition in team fights or escape when at low HP. If Shadow Demon has Aghanim's Sceptre it will also take away glaive bounces and extra damage from Luna's passive.
* Luna's illusions created by Disruption are very valuable with their Moon Glaives. These will effectively counter her pushing attempts and are painfully effective in team fights.
* Disruption can be used to save an ally from Eclipse.
* For the same reasons, Shadow Demon is a very good ally for Luna when they are in the same team.

* 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.

* A well-timed Doom prevents Nyx Assassin escaping with Vendetta and does not allow him to disengage with Spiked Carapace.
* Doom's high health also allows him to easily shrug off Nyx Assassin's burst damage and fend him off.

* Infernal Blade deals scaling damage and is useful against high HP targets such as Elder Titan. It also can interupt Echo Stomp if quick enough.
* Doom has very low base armor and naturally high HP, so he isn't significantly affected by Natural Order.

* In the laning stage, making illusions of Venomancer will turn his Poison Sting back at him, making for an easy gank at level one, and for later when your mid comes for ganks.

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

* Shadow Demon's Disruption will allow his allies to maneuver around you. It can also be used to protect an ally from your abilities, or Astral Imprisonment - Meteor Hammer combo.
* Disseminate turns your high damage Arcane Orb and Sanitiy's Eclipse against you and your teammates.
* Scepter upgraded Demonic Purge will break your Essence Flux passive for 7 seconds, preventing you from regaining mana, and severely hindering your damage output.

* The constant dispel from Demonic Purge will make any attempt to save the victim or himself by Surge become futile. For what it's worth, Demonic Purge will also dispel Ion Shell.

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

* Melee carries such as Sven, Ursa or Lifestealer can be slowed and easily kited with Demonic Purge.

Additional:
* Shadow Demon's Demonic Purge renders Ursa useless even through Black King Bar as it slows him, continually purges his Overpower charges and can not be dispelled by Ursa's Enrage.
* Disruption is a good way to save teammates against Ursa. Disrupting Ursa is also a good way to kite him, as it can not be dispelled by Enrage.

* 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.

* Heroes with summons or illusions can counter Flux, such as Beastmaster , Chen, or Shadow Demon.

* Doom can stop Death Prophet from casting spells, which makes her useless during team fights if she didn't cast Exorcism before the fight. Furthermore, Doom can use Scorched Earth to chase after her.

* 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 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.

* Shadow Demon with an Aghanim's Scepter will use Demonic Purge to disable Curse of Avernus and the passive component of Borrowed Time. If this is combined with a silence, Borrowed Time will not trigger at all.
* Even without Aghanim's Scepter, he can still waste Borrowed Time with Disruption. Curse of Avernus fully works on illusions, turning the passive ability against him.

* Heroes that lose a great amount of their tankiness and become easier to finish off: Bristleback, Spectre, Phantom Assassin, Enchantress, Dragon Knight.
* Once you have an Aghanim's Scepter, Shadow Demon instantly reaches a new power spike and becomes a counter for a variety of heroes that have strong passives.
* Heroes that lose a great amount of their tankiness and become easier to finish off: Bristleback, Spectre, Phantom Assassin, Enchantress, Dragon Knight.
* Heroes that lose a great amount of damage output and become less threatening: Phantom Assassin, Sven, Slark, Phantom Lancer.
* You can always stack camps and farm the scepter with Shadow Poison.

* Similarly, they can negate your X Marks The Spot & Torrent combo by protecting your target when you use Return. Good candidates to negate your combo include Outworld Destroyer and his Astral Imprisonment, and Shadow Demon and his Disruption.
* Heroes with hide abilities can often dodge a Ghostship just before it hits.
* Similarly, they can negate your X Marks The Spot & Torrent combo by protecting your target when you use Return. Good candidates to negate your combo include Outworld Destroyer and his Astral Imprisonment, and Shadow Demon and his Disruption.
* A Eul's Scepter of Divinity can also do the trick, but, unlike the previously mentioned abilities, you can only use it on yourself and not your allies.

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

* Heroes with ways to protect themselves or allies from Spirit Breaker's initiation: Shadow Demon

* Heroes with silences: Puck, Doom, Riki.

* Primal Beast really suffers against supports he cannot bully in the lane; this includes Dazzle, Shadow Demon and Dark Willow since they can use their respective abilities to stop Primal Beast from dealing burst damage, or make it hard for him to stay in range.

* Heroes with high physical damage output but lack of reliable escape mechanisms are always a good target for a solo gank: Sniper, Shadow Fiend, Troll Warlord, Drow Ranger. Those heroes, however, are dangerous if they manage to close the gap, so take caution.

* 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.

Additional:
* Be ready to save an ally from Omnislash with your Disruption.
* Spawning Juggernaut's illusions is a great deal, as his base attack time is low and he has a critical strike. Illusions will benefit from both.
* Demonic Purge will prevent Juggernaut's desperate attempt to flee using Blade Fury. However, it cannot stop him if he is using Town Portal Scroll.

* Supports with useful teamfight or contribution spells will be helpless against Doom: Dazzle, Oracle, Warlock.

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

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

* Heroes that lose a great amount of damage output and become less threatening: Phantom Assassin, Sven, Slark, Phantom Lancer.
* Once you have an Aghanim's Scepter, Shadow Demon instantly reaches a new power spike and becomes a counter for a variety of heroes that have strong passives.
* Heroes that lose a great amount of their tankiness and become easier to finish off: Bristleback, Spectre, Phantom Assassin, Enchantress, Dragon Knight.
* Heroes that lose a great amount of damage output and become less threatening: Phantom Assassin, Sven, Slark, Phantom Lancer.
* You can always stack camps and farm the scepter with Shadow Poison.

* Heroes that can punish aggressive heroes, such as: Leshrac, Shadow Demon, Pugna, Death Prophet.

* Supports with useful teamfight or contribution spells will be helpless against Doom: Dazzle, Oracle, Warlock.

* Disruption can protect Shadow Demon's allies from Fortune's End, preserving healing or buffs. It can also catch Oracle's allies, allowing Shadow Poison to be used without being dispelled.
* Demonic Purge prevents over-time healing during False Promise, such as Purifying Flames and Urn of Shadows. If he has Aghanim's Scepter, this issue can persist for longer or on multiple allies.
* It will not, however, prevent healing from instant abilities, items, or auras, making Mekansm a good choice against him.

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

* 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 Heavenly Grace 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.

* Heroes that can purge buffs can dispel Guardian Angel: Invoker, Shadow Demon, Oracle.

Additional:
* Demonic Purge can dispel Guardian Angel on the key target during combat, allow your allies to finish them.

* Heroes who can summon illusions and summons because Terrorblade has no abilities to deal with multiple enemies at once outside Reflection: Shadow Shaman, Naga Siren, Broodmother, Lycan, Enigma, Chaos Knight, Phantom Lancer, Shadow Demon, Dark Seer, Nature's Prophet, Invoker, Morphling, Visage, Grimstroke with Aghanim's Scepter.

* Heroes with break abilities: Shadow Demon (with Aghanim's Scepter), Viper.

* Alchemist is a well-known Radiance carrier among other auras your illusions will benefit from. They also get the extra move speed and reduced base attack time from his Chemical Rage, and it's even better if you can catch him as his own rage is about to expire.
* Disruption will buy enough time for all allies to retreat when Alchemist starts to activate Unstable Concoction.

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

* Ember Spirit cannot use his Activate Fire Remnant to escape while under effect from Doom.

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

* Disruption can save an ally from a fatal Reaper's Scythe.
* Demonic Purge can remove Ghost Shroud, making Necrophos vulnerable to physical damage and preventing him from regenerating health.

* An Aghanim's Scepter upgraded Doom 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 prevent him from using Dark Rift to escape

* Heroes who can hide the Dueled target (Outworld Destroyer, Shadow Demon, Tusk, Phoenix with Aghanim's Scepter etc).

Additional:
* Disruption can save allies and mess up an initiation from an enemy Legion Commander. Using Disruption on your ally that is affected by Duel will leave her totally exposed without the benefit of the life steal from Moment of Courage. A precise decision to Disrupt Legion Commander or her victim is crucial to waste Duel's potential.
* Demonic Purge cannot be dispelled by a hard dispel from Press the Attack, which in turn can be dispelled by your ultimate.

* Heroes that can instantly kill creeps greatly reduce the effectiveness of Chen's converted army: Lifestealer, Doom, Mirana, Clinkz.