Dark Seer
* Dark Seer's only disable is Vacuum. Though he starts off with high armor and health, he'll eventually have a hard time dealing with high mobility heroes such as 
Weaver or 
Queen of Pain.
Brewmaster
* Brewmaster is slow and has low armor, making his laning stage very difficult against Geminate Attack.
* Apart from the slow moving 
Hurl Boulder, which can be disjointed, he has no control to catch Weaver.
Dark Seer
* 
Spell Steal will easily steal all abilities from Dark Seer.
Additional:
* Spell Steal can perfect from Rubick's steal all abilities from Dark Seer. Rubick's always purchase 
Aghanim's Scepter can two stolens abilities from Dark Seer's and waiting for seconds for second stolen abilities (example: combinated Vacuum and Wall of Replica) and many different combination.
* A good positoning from Rubick's Spell Steal waiting steal abilities from Dark Seer 
Wall of Replica and illusion from Wall of Replica Dark Seer's can fighting with effect from outcome steal Wall of Replica from Rubick's.
* Combinated Rubick's steal 
Surge and 
Blink Dagger is very important catch from Dark Seer's and enemies.
* Rubick's 
Telekinesis can lifted up Dark Seer or enemy heroes and throw to Wall of Replica from Rubick's steal.
Brewmaster
* Heroes with strong team-fight abilities (especially ultimates) like 
Tidehunter, 
Brewmaster, 
Death Prophet, etc.
Dark Seer
* Dark Seer's only disable is Vacuum. Though he starts off with high armor and health, he'll eventually have a hard time dealing with high mobility heroes such as Weaver or Queen of Pain.
Brewmaster
* Blinking heroes like 
Anti-Mage or Queen of Pain can often chase down an injured Brewmaster after his ultimate expires.
Dark Seer
* 
X Marks the Spot prevents Dark Seer or his allies from escaping with Surge.
Dark Seer
* 
Fortune's End dispels Ion Shell and Surge, making any gank attempt on Dark Seer in the laning phase likely to succeed.
* 
Fate's Edict prevents all magical damage that comes from Dark Seer's abilities.
* Fortune's End dispels Ion Shell on creeps, which Dark Seer relies on to farm and zone.
Additional:
* Fortune's End can dispel 
Ion Shell, a skill that helps Dark Seer immensely in the laning phase, as well as Surge, a move-speed buff, effectively allowing Oracle to control Dark Seer, especially in the laning phase.
Brewmaster
* 
Hex's instant cast time will force Brewmaster into the awkward situation of needing some form of spell immunity or block to prevent being immediately hex upon blinking in, or wait until Shaman has used all his crowd control before entering a fight.
* Brewmaster also has no defense against Shadow Shaman lockdowns.
Brewmaster
* Outworld Destroyer's pure damage will mop up Primal Split's units very quickly.
Brewmaster
* After Brewmaster has committed Thunder Clap and Cinder Brew to gank, Bane can use 
Nightmare on Brewmaster to wait out the debuffs, and might even turn the tables by buying time for allied reinforcements.
* Bane can also prevent Brewmaster from using Primal Split with his long disables.
Brewmaster
* 
Ancient Seal's instant cast time will often silence Brewmaster before he can do anything.
* Brewmaster also has no defense against Skywrath Mage's massive magical damage.
Brewmaster
* 
Exorcism kills Primal Split's units very quickly.
Dark Seer
* 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.
Dark Seer
* A Sniper who is somewhat competent at positioning is hardly going to be affected by any of Dark Seer's spells thanks to 
Take Aim.
* However, an illusion of Sniper made with Wall of Replica is extremely powerful, and hard to deal with.
Brewmaster
* 
Hex's instant cast time will force Brewmaster into the awkward situation of needing some form of spell immunity or block to prevent being immediately hex upon blinking in, or wait until Lion has used all his crowd control before entering a fight. His direct magic burst also makes Brewmaster's Drunken Brawler worthless versus Lion.
Dark Seer
* 
Flame Guard makes Dark Seer not deal any damage with his skills to Ember Spirit.
Dark Seer
* Heroes with fast movement abilities will suffer huge damage when afflicted by Rupture: 
Spirit Breaker, 
Earth Spirit, 
Dark Seer.
Additional:
* 
Rupture can deal a lot of damage to either a surged Dark Seer or his allies and prevent the target from getting into position.
Dark Seer
* Abilities that deal low damage with high amounts of instances are irrelevant against Pudge during Flesh Heap's active: 
Gyrocopter's 
Rocket Barrage and Dark Seer's Ion Shell are just a couple examples.
Dark Seer
* In general, melee 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.
Dark Seer
* Strong laners are usually at a disadvantage because of how well Sven can jungle. Heroes such as Dark Seer. 
Underlord and Legion Commander may find that later Sven takes care of them very quickly after some jungle farming.
Dark Seer
* Ion Shell destroys 
Refraction's protection stacks in short time.
* Surge ignores the massive slow from 
Psionic Trap.
Brewmaster
* The three Primal Split brewlings all attacking Templar Assassin at once will remove her Refraction quickly, especially with Fire's Permanent Immolation.
* Templar Assassin has no way to stop Brewmaster from using Primal Split by herself, and may get unlucky and miss her 
Meld if trying to burst him during her ally's disable.
Dark Seer
* Ion Shell zones out Broodmother in the laning phase, and can kill her spiderlings if used on one Spiderling in a group.
* 
Vacuum can pull Broodmother out of the treeline.
Additional:
* Ion Shell is a very powerful weapon against Broodmother's Spiderlings and makes her laning much harder.
Brewmaster
* Heroes who produce many summons will have a hard time against Storm's Dispel Magic during teamfight: 
Broodmother, 
Enigma, 
Nature's Prophet.
Dark Seer
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: 
Venomancer, 
Huskar, 
Ember Spirit, Dark Seer, 
Sand King, Doom, 
Dawnbreaker. However, this also means they are easily stunned.
Brewmaster
* 
Cyclone from Storm in 
Primal Split can waste Nyx's Spiked Carapace, since its duration is shorter than the Cyclone's.
Dark Seer
* Heroes that rely on illusions typically spawn very strong illusions inside Dark Seer Wall of Replica that he can use against them or their team: 
Phantom Lancer, 
Chaos Knight, 
Naga Siren, 
Terrorblade.
Brewmaster
* Storm's Dispel Magic combined with Thunder Clap deals high damage against Chaos Knight's illusions even in the late game.
* Chaos Knight's reliance on physical damage is easily hindered by Drunken Brawler.
* Chaos Knight's lack of area effect and mobility makes him easily overwhelmed by Primal Split.
Additional:
* 
Dispel Magic from {U:Storm} can instantly kill Phantasms early on, and can still deal a lot of damage to them late game, revealing the real Chaos Knight.
Dark Seer
* With 
Normal Punch from Aghanim's Scepter, Dark Seer can gain an advantage against heroes who rely on evasion as Normal Punch has true strike: 
Phantom Assassin, 
Windranger, 
Hoodwink.
Brewmaster
* In general, Brewmaster's Cinder Brew and Thunder Clap makes him good against physical damage carries: 
Ursa, 
Clinkz, 
Faceless Void, 
Troll Warlord, 
Templar Assassin, Phantom Assassin.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: 
Beastmaster, Broodmother, Enigma, Nature's Prophet, 
Visage, 
Warlock, Wraith King.
Brewmaster
* Heroes who produce many summons will have a hard time against Storm's Dispel Magic during teamfight: Broodmother, Enigma, Nature's Prophet.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Brewmaster
* Heroes who produce many summons will have a hard time against Storm's Dispel Magic during teamfight: Broodmother, Enigma, Nature's Prophet.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Brewmaster
* Heroes with area dispel can kill multiple skeletons at once: Brewmaster, 
Oracle.
Dark Seer
* Dark Seer's Vacuum and Ion Shell allows him to clear a wave of Terrorblade's illusions.
* Because Terrorblade often builds items that require 
Ultimate Orb like 
Manta Style and 
Eye of Skadi, Dark Seer can create a very strong illusion of Terrorblade with Wall of Replica and Normal Punch from Aghanim's Scepter.
* If Dark Seer can use Vacuum to help teammates land their AoE abilities, Terrorblade will be quickly killed before he even gets a chance to use Sunder.
Additional:
* Dark Seer's Vacuum and Ion Shell allows him to clear a wave of Terrorblade's illusions.
* Because Terrorblade often builds items that require Ultimate Orb like Manta Style and Eye of Skadi, Dark Seer can create a very strong illusion of Terrorblade with Wall of Replica and Normal Punch from Aghanim's Scepter.
* If Dark Seer can use Vacuum to help teammates land their AoE abilities, Terrorblade will be quickly killed before he even gets a chance to use Sunder.
Brewmaster
* If Ursa uses 
Enrage Brewmaster can use Cyclone to render him harmless during his ultimate.
* Brewmaster has two spells to slow down Ursa, allowing his team to kite around him easily.
Brewmaster
* Dispel Magic from {U:Storm} instantly removes Heavenly Grace and Guardian Angel from Omniknight's allies in its radius of effect.
Brewmaster
* Primal Split makes Brewmaster invulnerable for the duration, rendering effects of Cold Feet and Ice Blast useless.
* Dispel Magic can dispel Cold Feet from allies.
* Brewmaster can easily run Ancient Apparition down with the slow from 
Thunder Clap and 
Cinder Brew.
Brewmaster
* Brewmaster can waste a large portion of Lycan's ultimate by putting him in Cyclone.
* Lycan has no way to stop Brewmaster from using Primal Split by himself.
* Lycan's team often tries to push towers as a group, and Brewmaster excels at winning teamfights while trying to defend a tower.
Dark Seer
* Venomancer is a low health hero and low range hero who is easy to harass with Ion Shell on a creep in the early game.
* Venomancer depends entirely on all his slows to keep distance or chase, but since Surge ignores slows, it is nearly impossible for Venomancer to hunt or run away from Dark Seer or his surged teammates.
Brewmaster
* Brewmaster can use Cyclone to disable Huskar's healer for much longer than most other heroes can, to make Huskar vulnerable.
* Huskar has no way to stop Brewmaster from using Primal Split by himself, but can cut a good amount of his high health away if Huskar's team wants to burst Brewmaster down during a different disable.
Brewmaster
* {U:Earth} has passive 
Spell Immunity, allowing him to walk into the Echo Stomp radius to stun Elder Titan with his Hurl Boulder.
* {U:Storm}'s Cyclone can cancel the channeling of Echo Stomp and take Elder Titan out of the fight for {show:A|Storm|Cyclone|value2} seconds.
Brewmaster
* {U:Storm} can use Cyclone on Abaddon when he activates Borrowed Time, wasting its duration.
* 
Drunken Brawler and Thunder Clap hinder Abaddon from applying Curse of Avernus' silence on him.
Additional:
* Dispel Magic can remove Abaddon's 
Aphotic Shield or 
Curse of Avernus on an allied hero.
* Cyclone's lengthy duration wastes much of 
Borrowed Time's duration.
Dark Seer
* Dark Seer's Vacuum and Ion Shell can clear a wave of Chen's Creeps effectively.
* Surge applies haste movement and negates the slow from 
Penitence, allowing Dark Seer to easily escape from Chen and his creeps.
* Dark Seer's full combo from Dark Seer's Vacuum, Wall of Replica and Normal Punch from Aghanim's Scepter can often kill Chen or any of his allies before he can save them with 
Hand of God.
Additional:
* Dark Seer's Vacuum and Ion Shell can clear a wave of Chen's Creeps effectively.
* Surge applies haste movement and negates the slow from Penitence, allowing Dark Seer to easily escape from Chen and his creeps.
* Dark Seer's full combo from Dark Seer's Vacuum, Wall of Replica and Normal Punch from Aghanim's Scepter can often kill Chen or any of his allies before he can save them with Hand of God.
Dark Seer
* 
Living Armor can be destroyed quickly with Ion Shell.
Dark Seer
* Dark Seer can take great advantage of 
Divided We Stand by putting an Ion Shell on a clone in order to harass them effectively.
* Vacuum can take a single Meepo and disable him for Dark Seer and his teammates to take out.
Brewmaster
* Brewmaster can make the Spirit Bear a much smaller threat with Cinder Brew.
* Cyclone removes the bear from a fight so that his team can easily focus on the hero.
* While most heroes would be worn down by a Spirit Bear 
Radiance in the time it takes to kill Lone Druid, Brewmaster is protected in Primal Split.
Dark Seer
* Heroes with haste can negate Enchant's slow: Weaver, Dark Seer, 
Lycan, 
Centaur Warrunner.
Dark Seer
* Certain heroes can mess up with Pangolier's positioning and timing (especially if he intends to use Rolling Thunder during combat): 
Vengeful Spirit, 
Keeper of the Light, Huskar, Dark Seer
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Dark Seer
* Dark Seer can increase the movement speed of allies with Surge, breaking Static Link.
Dark Seer
* With Normal Punch from Aghanim's Scepter, Dark Seer can gain an advantage against heroes who rely on evasion as Normal Punch has true strike: Phantom Assassin, Windranger, Hoodwink.
Dark Seer
* Heroes with hastes: Dark Seer, Lycan
Dark Seer
* With Normal Punch from Aghanim's Scepter, Dark Seer can gain an advantage against heroes who rely on evasion as Normal Punch has true strike: Phantom Assassin, Windranger, Hoodwink.
Dark Seer
* Heroes who do not have nor rely on passive abilities make Nethertoxin much less effective: Clinkz, 
Pugna, Nature's Prophet, Dark Seer, Lycan, 
Tusk
Brewmaster
* In general, Brewmaster's Cinder Brew and Thunder Clap makes him good against physical damage carries: Ursa, Clinkz, Faceless Void, Troll Warlord, Templar Assassin, Phantom Assassin.
Additional:
* Thunder Clap and Drunken Brawler prevent Faceless Void from maximising his damage potential in fights.
* Cyclone disables Faceless Void during Chronosphere or in general.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Additional:
* Surge allows for Dark Seer and his allies to escape from Upheaval due to it ignoring any slow.
Dark Seer
* The haste provided by Dark Seer's Surge or a {Rune:Haste} renders your slows ineffective.
Dark Seer
* Heroes with escape abilities : Anti-Mage Dark Seer 
Slark 
Storm Spirit Windranger Weaver can kite Lifestealer due to him having no lockdown
Brewmaster
* In general, Brewmaster's Cinder Brew and Thunder Clap makes him good against physical damage carries: Ursa, Clinkz, Faceless Void, Troll Warlord, Templar Assassin, Phantom Assassin.
Dark Seer
* Heroes that rely on illusions typically spawn very strong illusions inside Dark Seer Wall of Replica that he can use against them or their team: Phantom Lancer, Chaos Knight, Naga Siren, Terrorblade.
Dark Seer
* Heroes that rely on illusions typically spawn very strong illusions inside Dark Seer Wall of Replica that he can use against them or their team: Phantom Lancer, Chaos Knight, Naga Siren, Terrorblade.
Additional:
* Ion Shell helps taking down illusions quickly, making it easy to identify the real Phantom Lancer.
* Surge allows Dark Seer and his teammates to run away from Phantom Lancer, who relies on his 
Phantom Rush to chase enemies.
Brewmaster
* In general, Brewmaster's Cinder Brew and Thunder Clap makes him good against physical damage carries: Ursa, Clinkz, Faceless Void, Troll Warlord, Templar Assassin, Phantom Assassin.
Dark Seer
* Dark Seer can pull together Spectre's illusions with Vacuum, and Wall of Replica creates an illusion of Spectre that deals massive damage.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Dark Seer
* In general, heroes who are melee with no way to fight back can be very easily poked by Monkey King to gain his Jingu Mastery stacks: Dark Seer, 
Riki, 
Rubick.
Brewmaster
* Cinder Brew and Drunken Brawler makes it hard for Monkey King to stack Jingu Mastery.
* Cyclone can remove Monkey king for 6 seconds if his allies lack dispels.
* Dispel Magic can dispel Jingu Mastery's bonuses.
Dark Seer
* Dark Seer relies on Surge for most of his mobility, so he's not very vulnerable to slows, but much more to root effects and walls or pseudo-walls such as 
Disruptor's 
Kinetic Field or Slark's 
Pounce.
Brewmaster
* Brewmaster with Primal Split
* Heroes that can dodge Glimpse:
* 
Puck with 
Phase Shift
* Riki with 
Tricks of the Trade
* Phantom Lancer with 
Doppelganger
* Ember Spirit with 
Sleight of Fist and 
Activate Fire Remnant
* Chaos Knight with 
Phantasm
* Naga Siren with 
Mirror Image
* Tusk with 
Snowball
* 
Juggernaut with 
Omnislash
* Brewmaster with Primal Split
* 
Lifestealer with 
Infest
* 
Phoenix with 
Supernova
Dark Seer
* Dark Seer relies on Surge for most of his mobility, so he's not very vulnerable to slows, but much more to root effects and walls or pseudo-walls such as Disruptor's Kinetic Field or Slark's Pounce.
Dark Seer
* Heroes with AoE abilities will hit Slark in Shadow Dance: 
Lina, 
Jakiro, Underlord, 
Leshrac, Dark Seer, 
Earthshaker, 
Timbersaw, 
Crystal Maiden.
Dark Seer
* Dark Seer's strength lies in his high-mana cost skills. So
Mana Break can be a great nuisance for him, since it can reduce his mana and prevent him from casting his spells.
Mana Void can deal a lot of damage if Dark Seer spent a lot of mana on his abilities.
*
Brewmaster
* Blinking heroes like
Anti-Mage or 
Queen of Pain can often chase down an injured Brewmaster after his ultimate expires.