* Ice Blast nullifies the health regeneration granted by Chemical Rage, which Alchemist greatly relies on to stay alive in battle.
* Alchemist tends to build Armlet of Mordiggian which can be deadly during Ice Blast.
Additional:
* Ice Blast cancels out Chemical Rage's rapid health regeneration. It can also take advantage of Alchemist's Armlet of Mordiggian toggling, as it will make HP drain insanely fast, essentially killing the bearer in no time.

* Ice Blast prevents Lifestealer from lifestealing and healing with Infest in fights.

* Alchemist's reliance on fast attack speed to do single-target damage makes him vulnerable to Static Link. It also goes through Black King Bar, which is a standard item on Alchemist.
* Eye of the Storm is great against high health strength heroes as it reduces their survivability to physical damage.
* Razor has early lane push to counter Acid Spray.

* Static Link cannot be dispelled by Rage or Infest, so Razor will be able to track Lifestealer down during an attempted escape.
* Storm Surge makes it hard for Lifestealer to catch Razor.
* Static Link can stop Open Wounds from getting any additional lifesteal, but keep in mind Lifestealer can still utilize Feast.
* Eye of the Storm penetrates the spell immunity of Rage.

* Dark Pact can be used to remove Open Wounds.
* Shadow Dance allows Slark to attack Lifestealer for its duration without any way for Lifestealer to fight back.
* Slark commonly buys a Silver Edge, which can break Lifestealer's Feast, severely diminishing his damage output and lifesteal.

* Shadow Dance allows Slark to not be targeted by Unstable Concoction, making Alchemist stun himself and making himself vulnerable to the enemy.
* Dark Pact also allows him to just purge off the stun if timed correctly.
* Essence Shift will steal stats over long durations at a time should Alchemist lack the damage to kill Slark.

* Untouchable greatly reduces Chemical Rage's attack speed advantage.

* Since Untouchable pierce Spell immunity, Lifestealer cannot burst her down even with Rage ; meaning she can heal herself back to full HP.

* Heroes without an escape mechanism: Shadow Fiend, Alchemist

Additional:
* Chemical Rage will rarely save Alchemist against Ursa's Fury Swipes.
* Enrage allows Ursa to both be a threat to Alchemist and avoid his over time damage.

* Lifestealer can't fight Ursa in any stage of the game because of his high physical damage with Fury Swipes and Overpower.
Additional:
* Lifestealer's Feast will most likely not out-heal the damage from Fury Swipes and Overpower in the early to mid game.

* Heroes with high physical damage can damage Lifestealer more than he can heal: Bristleback, Clinkz, Luna,Shadow Fiend, Slardar {Hero ID:Terrorblade}

* Corrosive Haze followed by Slithereen Crush takes advantage of Alchemist's main weakness, being physical damage before he has the change to improve his surviability with items.
* Bash of the Deep will deal lots of damage during the laning phase.

* Clinkz can use Burning Army in teamfights which will cause a problem for Alchemist.

* Clinkz relies heavily on the physical damage provided by Searing Arrows, which completely overrides the capabilities of Rage.
* Open Wounds is near worthless against Clinkz as he can instantly run away with Skeleton Walk before returning later on.
* Clinkz, by nature will often build items that Lifestealer hates dealing with such as physical damage items like Desolator or Daedalus and instant silences or hexes from Bloodthorn and Scythe of Vyse.

* 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.

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

* Primal Roar pierces Rage and can disable Lifestealer in fights.

* Lacking any stun and being heavily dependent on his physical attacks and spell immunity, Lifestealer has no way to stop Black Hole, assuming he does not initiate Enigma first with Abyssal Blade.
* Enigma's abilities, with exception of Malefice, can pierce spell immunity and deal pure damage (and percentage-based damage in Midnight Pulse's case), putting Lifestealer in potentially adverse situations.

* Reaper's Scythe can kill Alchemist before Chemical Rage has the time to heal him.
* Ghost Shroud can prevent Alchemist from attacking Necrophos, as well as make him immune to Acid Spray and Unstable Concoction damage.
* Heartstopper Aura will do damage as long as Necrophos is alive based on health percentage, which is a problem for a strength hero such as Alchemist.

* The Swarm is not blocked by Rage and can be used to lower Lifestealer's already low armor, making him even more vulnerable to physical damage.
* Shukuchi renders the Open Wounds slow pretty useless, as it gives Weaver maximum movement speed, allowing him to escape or kite around Lifestealer.
* However, Weaver is a common Linken's Sphere carrier to block and Time Lapse to dispel Open Wounds.
Additional:
* Open Wounds's slow is ignored by Shukuchi.
* Lifestealer has no other lockdown and relies on being on top of enemies; Weaver can kite him with ease.

* Lifestealer's low mobility makes him easy to kite.
* Stone Gaze pierces Rage, wasting its cooldown and making Lifestealer unable to fight.

* Lifestealer cannot use Rage, Infest or Open Wounds when affected by Smoke Cloud's silence, and Feast cannot heal him effectively because of the blind, leaving him very weak both offensively and defensively.
* Infest ganks are harder when the enemy team has a Riki, as there are often only four heroes on the map that you can initiate on.

* Chaos Knight's Level 20 Talent: Reality Rift Pierces Spell Immunity allows for quick bursting down of Lifestealer during his Rage.
* Phantasm dispels Open Wounds.
* Lifestealer has no way of dealing with Chaos Knight's illusions.
Additional:
* Level 20 talent allows Reality Rift to bypass spell immunity provided by Rage, thus negating the advantage Lifestealer has in his kit.
* Lifestealer lacks wave clearing and reliable lockdown makes it difficult to fight Chaos Knight's illusion.
* Feast is largely negated by Chaos Knight's high burst damage in Chaos Strike.

* Skywrath Mage can easily harass Alchemist in the laning phase with multiple Arcane Bolts. Additionally, if Alchemist is in the process of throwing an Unstable Concoction, and has no way to dispel Ancient Seal, the self stun becomes an easy set up for Mystic Flare.
* Caution, however, as a decently farmed Alchemist with {Item ID:Radiance} and {Item ID:Manta Style} can easily send illusions to harass and force Skywrath Mage out.

* Although he can avoid Eclipse with Rage and Infest, Luna's physical damage can be enough to deal with him.
* Manta Style is a common pick on Luna, which can help her dispel Open Wounds. In addition, Lifestealer is not good against illusions created by Manta Style.

* Chronosphere provides excellent lockdown against Rage.
* Faceless Void's Time Lock stops Lifestealer from getting health regeneration from auto-attacks

* Lifestealer relies on Open Wounds to slow enemies to burst them, but Windranger can use Windrun to escape through Open Wounds duration.
* Windrun and Focus Fire can easily allow Windranger to kite Lifestealer and do good amounts of damage in the process.

* The passive armor provided by Berserker's Rage makes Troll Warlord resilient to Feast in early game.
* The 60% miss chance given by Whirling Axes (Melee) is useful when Rage is not active.
* Battle Trance can purge Open Wounds, negating a large amount of Lifestealer's sustain in fights.

* Ember's magic damage build is able to burst down Alchemist due to his low strength gain and Alchemist's normal item pick up.

* Alchemist has very bad armor and does not build armor items for the large majority of his build, so Jingu Mastery and Wukong's Command can be very deadly.
* Desolator, Sange and Yasha or Diffusal Blade can all be purchased to increase your damage against Alchemist or just to keep your movement speed high enough to match him while Chemical Rage is active.
* Monkey King is an agility hero and scales with armor, so Acid Spray loses it's effectiveness later in the game.

* Heroes that lack burst damage will have a difficult time taking down Monkey King, and fare badly against Jingu Mastery: Legion Commander, Lifestealer, Weaver, Wraith King

* Terrorblade's illusions and ranged attacks in Metamorphosis can burst down Lifestealer very quickly.
* Terrorblade has low health due to his low strength gain, which reduces Feast's lifesteal and damage.
* Terrorblade's high armor makes Lifestealer's Desolator useless.
* Because Lifestealer usually walks around with high HP in fights due to his lifesteal (and sometimes Armlet of Mordiggian), he is a great target for Terrorblade's Sunder.
Additional:
* Reflection's illusion carries Feast as well, making it useful in fights.
* Feast cannot compensate for Terrorblade's incoming high damage, due to his low Strength gain.
* Open Wounds is a lot harder to land on the real Terrorblade if he has illusions around him.
* Lifestealer relies on right-clicks to deal damage, and Terrorblade's high armor can reduce his damage by quite a bit.

* Lifestealer is a great target for Morphling to use Morph, as he can use Rage to gain spell immunity and a movement speed boost.
* Morphling's high armor also makes Lifestealer's attacks do less damage.

* Heroes with summons: Lycan, Broodmother, Visage.

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

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

* Heroes with illusions: Chaos Knight, Naga Siren, Phantom Lancer

* Heroes with summons: Lycan, Broodmother, Visage.

* Visage can quickly kill heroes with low to medium base armor and no innate escape mechanism. Examples include Alchemist, Crystal Maiden and Zeus.

* Chaotic Offering can stop heroes who like to use spell immunity and teleport scrolls to safely farm during the early to mid game, since it stuns and also goes through spell immunity. Notable examples: Juggernaut, LifeStealer.

* Many physical-only single-target heroes like Lifestealer, Sven, Wraith King, Phantom Assassin, Templar Assassin etc.

* Heroes who can delivers a big chunk of damage in few hits will find themselves struggle against Templar Assassin's Refraction: Sven, Phantom Assassin, Ursa, Wraith King, Lifestealer

* With the exception of Magic Missile (unless the player takes the Level 25 Talent "Magic Missile Pierces Spell Immunity"), all of Vengeful Spirit's spells ignore Spell Immunity. This also makes her good against heroes with built-in Spell Immunity like Lifestealer or Juggernaut or heroes that tend to pick up Black King Bar, like Sven.

* Pugna's Decrepify makes sure that either Alchemist is unable to hit anyone while also being slowed and susceptible to magical damage, or can protect an ally from physical attacks. Besides, Pugna can push early on, when Alchemist is not strong enough to repel it, so by the time Alchemist comes online, he might be forced to sit in base.

* Heroes with high physical damage can damage Lifestealer more than he can heal: Bristleback, Clinkz, Luna,Shadow Fiend, Slardar {Hero ID:Terrorblade}

* Heroes with high physical damage can damage Lifestealer more than he can heal: Bristleback, Clinkz, Luna,Shadow Fiend, Slardar {Hero ID:Terrorblade}

* Heroes who rely on skills to become a heavy hitter in a certain amount of time can waste their timing because of a lucky Lucky Shot's disarm: Terrorblade, Sven, Clinkz, Windranger, Alchemist, Dragon Knight, Legion Commander

* Melee heroes that get kited easily have hard times dealing with Puck without any lockdowns, as Puck is one of the most mobile heroes. Heroes like Sven, Lifestealer, Ursa and Alchemist may have problems to get to Puck without proper initiation items. They also lack reliable lockdowns, as their disables are easily avoidable for Puck, or are just a soft disable.

* Melee heroes that get kited easily have hard times dealing with Puck without any lockdowns, as Puck is one of the most mobile heroes. Heroes like Sven, Lifestealer, Ursa and Alchemist may have problems to get to Puck without proper initiation items. They also lack reliable lockdowns, as their disables are easily avoidable for Puck, or are just a soft disable.

* Heroes that rely on physical damage are ineffective against Dragon Knight due to his high armor: Phantom Assassin,Bloodseeker, Lifestealer, Troll Warlord

* Sprout is good for trapping melee carries with no escape abilities: Sven, Ursa, Alchemist, Lifestealer etc.

* Sprout is good for trapping melee carries with no escape abilities: Sven, Ursa, Alchemist, Lifestealer etc.

* Aside from his ultimate, Lifestealer has no AoE abilities to deal with Phantom Lancer's illusions, nor does he have the mobility to escape Phantom Rush.
* Doppelganger dispels Open Wounds.
* Phantom Lancer usually builds Diffusal Blade, which a problem for a low already mana hero like Lifestealer.
Additional:
* Doppelganger dispels Open Wounds.
* Lifestealer has no way of dealing with Phantom Lancer's illusions.
* Phantom Lancer also commonly builds Diffusal Blade, which poses a large problem to Lifestealer and his low mana pool.