Beastmaster
* Heroes with Linken's Sphere as core item: 
Weaver, 
Morphling, 
Medusa.
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.
Beastmaster
* 
Primal Roar can be instantly dispelled by Aphotic Shield.
* The debuffs from 
Wild Axes and 
Poison from 
Call of the Wild: Boar can also be dispelled by Aphotic Shield.
Additional:
* 
Aphotic Shield effectively nullifies Primal Roar's single-target initiation on allies.
* Even being initiated by Primal Roar, 
Borrowed Time can make Abaddon extremely difficult to kill.
Beastmaster
* 
Cold Embrace mitigates Primal Roar's single-target initiation on allies.
* 
Winter's Curse can turn Beastmaster's summons and Inner Beast against his teammate.
Additional:
* Beastmaster's summons and 
Inner Beast are very useful to attack his cursed teammate.
* Cold Embrace effectively mitigates Primal Roar's single-target initiation on allies.
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.
Beastmaster
* Having many summons out will cause 
Echo Slam to deal extra damage.
Dark Seer
* 
X Marks the Spot prevents Dark Seer or his allies from escaping with Surge.
Beastmaster
* 
Reactive Armor is very effective against Beastmaster's summons during laning stage and entire game.
* Timbersaw can quickly clear Beastmaster's summons with his nukes.
* 
Lotus Orb item for Timbersaw can releases roar from the target position, stunning and damaging Beastmaster and knocking away, damaging and slowing allies that stand on the way.
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.
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.
Beastmaster
* 
Frostbite kills boars instantly on the laning stage leading to either experience lead or disabling Beastmaster from using Boar
* 
Crystal Nova nukes and slows down the attack and movement speed of Beastmaster's summons.
* 
Freezing Field grants improved self armor, nukes and slows down Beastmaster and his summons.
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.
Beastmaster
* Heroes with Linken's Sphere as core item: Weaver, Morphling, Medusa.
Beastmaster
* Heroes who summon multiple units that are not spell immune. 
Nature's Prophet,
Lycan,
Beastmaster
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.
Beastmaster
* Heroes with summoned units don't fare well against Dawnbreaker. (
Phantom Lancer ,Beastmaster ,Lycan).
Beastmaster
* Heroes with strong dispels can remove Primal Roar's stun: 
Abaddon, Slark, 
Oracle.
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
* 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.
Beastmaster
* Heroes with AoE abilities are a bane to Beastmaster's summons: 
Storm Spirit, 
Magnus, 
Pangolier.
Beastmaster
* Heroes with Linken's Sphere as core item: Weaver, Morphling, Medusa.
Dark Seer
* 
Flame Guard makes Dark Seer not deal any damage with his skills to Ember Spirit.
Beastmaster
* Heroes who rely on high mobility are especially vulnerable to Primal Roar: Storm Spirit, 
Ember Spirit, Queen of Pain.
Beastmaster
* 
Illuminate clears Beastmaster's summons and is effective against his push.
Dark Seer
* Heroes with hastes: Dark Seer, Lycan
Beastmaster
* 
Untouchable negates Inner Beast's attack speed bonus, making her hard to kill even if stunned by Primal Roar.
* Enchantress can also take control of Beastmaster's summons.
Additional:
* 
Enchant can control Beastmaster's boars with Enchant, mitigating his effectiveness during the laning stage and teamfights.
Dark Seer
* Heroes with haste can negate Enchant's slow: Weaver, Dark Seer, Lycan, 
Centaur Warrunner.
Beastmaster
* Wild Axes, Primal Roar and 
Drums of Slom can deal high damage to Chen and clear waves of his creeps.
* Even though Chen can take control of the Boar from 
Call of the Wild Boar at any time with 
Holy Persuasion, which could put Beastmaster in a disadvantage against Chen. Skilled Beastmaster can buy 
Helm of the Overlord to regain control of it to counter this problem.
* Smart Beastmaster can also buy 
Bloodthorn to prevent Chen from taking control of the Boar from Call of the Wild Boar and make Chen more vulnerable to Beastmaster.
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.
Beastmaster
* Attacks from Boars and the attack speed boost from Inner Beast will quickly wear down 
Refraction.
Dark Seer
* Ion Shell destroys Refraction's protection stacks in short time.
* Surge ignores the massive slow from 
Psionic Trap.
Beastmaster
* Wild Axes destroys large amounts of trees specially upgraded with Aghanim's Scepter,
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.
Beastmaster
* Because only one clone needs to be killed in order to kill Meepo, heroes that excel at singling out enemies can also be a detriment to him, such as 
Batrider, Beastmaster, 
Pudge and 
Clockwerk.
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.
Beastmaster
* Wraith King's lack of area of effect spells makes him easily overwhelmed by Beastmaster's summons.
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.
Beastmaster
* Heroes with disables that ignore spell immunity will render Phantom Assassin completely useless in teamfights throughout the game: 
Axe, Enigma, 
Vengeful Spirit, 
Doom, 
Bane, Beastmaster, Pudge, Medusa, Warlock.
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.
Beastmaster
* Illusion or summon-based heroes can be a problem to Viper due to his lack of AoE damage: 
Naga Siren, Phantom Lancer, Beastmaster
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
Beastmaster
* Long ranged disables, especially those that pierce spell immunity, cancel Black Hole: Beastmaster's Primal Roar, Bane's 
Fiend's Grip, 
Faceless Void's 
Chronosphere, Magnus's 
Reverse Polarity, Axe's 
Berserker's Call, Pudge's
Meat Hook.
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'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.
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.
Beastmaster
* Primal Roar and the slow from Boars make kiting Tiny very easy.
Beastmaster
* Primal Roar allows Beastmaster to keep Lycan in place after he used his Shapeshift.
Beastmaster
* Primal Roar and the slow from Boars make kiting Troll Warlord very easy.
Beastmaster
* Inner Beast helps Beastmaster's team destroy 
Supernova quickly.
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.
Beastmaster
* Primal Roar and the slow from Boars makes kiting Ursa very easy.
Dark Seer
* 
Living Armor can be destroyed quickly with Ion Shell.
Beastmaster
* Beastmaster's Hawk can find Tinker easily while he is pushing or blinking into trees.
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.
Beastmaster
* Any long duration disables that can pierce through both, Pierce The Veil and 
Black King Bar are devastating against Muerta: Enigma's 
Black Hole, 
Dawnbreaker's 
Solar Guardian, Axe's Berserker's Call, Naga Siren's Aghanim's Scepter upgraded 
Ensnare and 
Reel In from Aghanim's Scepter, Jakiro's Aghanim's Scepter upgraded 
Macropyre, Bane's Fiend's Grip, Pudge's 
Dismember, Batrider's 
Flaming Lasso, Beastmaster's Primal Roar, 
Grimstroke's 
Soulbind, Medusa's 
Stone Gaze, Magnus's Reverse Polarity.
Beastmaster
* Heroes with AoE abilities are a bane to Beastmaster's summons: Storm Spirit, Magnus, Pangolier.
Beastmaster
* Heroes with other kind of disables that pierce spell immunity can hold Pangolier in place during Rolling Thunder: Axe, Beastmaster, Enigma, Magnus, Pudge, Batrider, Bane, 
Winter Wyvern
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 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 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 pull together Spectre's illusions with Vacuum, and Wall of Replica creates an illusion of Spectre that deals massive damage.
Dark Seer
* Dark Seer can increase the movement speed of allies with Surge, breaking Static Link.
Dark Seer
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: Jakiro, 
Viper, 
Venomancer, Huskar, Ember Spirit, Dark Seer, 
Sand King, Doom, Dawnbreaker. However, this also means they are easily stunned.
Beastmaster
* 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.
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.
Beastmaster
* 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.
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 Lich's 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.
Beastmaster
* Heroes who relies on illusions and summons (Beastmaster, Chaos Knight, etc.).
Beastmaster
* Heroes with illusions and summons can manfight Night Stalker: Terrorblade, Beastmaster, Broodmother.
Beastmaster
* Long lockdown is a great way to deal with Axe to prevent Berserker's Call from being used, heroes such as 
Legion Commander, Beastmaster and 
Primal Beast are good examples of this.
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.
Beastmaster
* Heroes with summons or illusions can counter Flux, such as Beastmaster , 
Chen, or 
Shadow Demon.
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.
Beastmaster
* The Hawk can easily find Monkey King while he is sitting on a tree.
* Wild Axes can knock out Monkey King from tree.
* Boars drastically reduce Monkey King's attack speed, making it harder for him to gain 
Jingu Mastery stacks.
Additional:
* Wild Axes can chop down trees, making it difficult for Monkey King to utilize Tree Dance well.
* 
Call of the Wild Hawk can scout Monkey King when he is perched on top of trees.
* Primal Roar can stun Monkey King for a lengthy duration even with spell immunity.
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.
Beastmaster
* Primal Roar takes Sven out of the fight completely, even with Black King Bar.
Beastmaster
* Single-target disablers will have difficulty locking down a Chaos Knight with Phantasm active: Bane, Beastmaster, 
Bloodseeker, Clockwerk, Doom, Shadow Shaman.
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.
Beastmaster
* Heroes with AoE abilities are a bane to Beastmaster's summons: Storm Spirit, Magnus, Pangolier.
Beastmaster
* Heroes who rely on high mobility are especially vulnerable to Primal Roar: Storm Spirit, Ember Spirit, Queen of Pain.
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.
Beastmaster
* Heroes who rely on high mobility are especially vulnerable to Primal Roar: Storm Spirit, Ember Spirit, Queen of Pain.
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.
Beastmaster
* Heroes with disables that go through spell immunity can end Bloodseeker before he has the chance to do anything: Batrider, Beastmaster
Dark Seer
* 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
* Heroes with strong area-of-effect damaging and/or disabling abilities will be able to intercept Underlord and his team when they exit from Fiend's Gate: 
Luna's Aghanim's Scepter upgraded 
Eclipse, Dawnbreaker's Solar Guardian, Axe's Berserker's Call, 
Mars's 
Arena of Blood, Jakiro's Macropyre, 
Dual Breath and 
Ice Path, Naga Siren's 
Song of the Siren, 
Razor's 
Eye of the Storm and 
Plasma Field, Lina's 
Light Strike Array, Broodmother's 
Spinner's Snare from Aghanim's Scepter, 
Elder Titan's 
Earth Splitter and 
Echo Stomp, Alchemist's 
Unstable Concoction and 
Acid Spray, Queen of Pain's 
Sonic Wave, Dark Seer's Wall of Replica and Vacuum, Venomancer's 
Noxious Plague and 
Poison Nova from Aghanim's Scepter, Oracle's 
Fortune's End and 
Rain of Destiny from 
Aghanim's Shard, Bloodseeker's 
Blood Rite, Enigma's Black Hole and 
Midnight Pulse, 
Shadow Fiend's 
Requiem of Souls, Batrider's Aghanim's Scepter upgraded Flaming Lasso, 
Firefly, 
Flamebreak and 
Sticky Napalm, 
Ancient Apparition's 
Ice Blast, Sand King's 
Epicenter, 
Sand Storm and 
Burrowstrike, Gyrocopter's 
Call Down, Ember Spirit's 
Sleight of Fist, 
Death Prophet's 
Exorcism and 
Silence, 
Monkey King's 
Wukong's Command, Crystal Maiden's Freezing Field, 
Muerta's 
The Calling, Medusa's Stone Gaze, 
Zeus's 
Nimbus from Aghanim's Scepter. 
Dark Willow's 
Bramble Maze, Pangolier's 
Swashbuckle, Grimstroke's Soulbind, 
Ink Swell and 
Stroke of Fate, Earthshaker's Echo Slam and 
Fissure, 
Puck's 
Dream Coil and 
Waning Rift, Winter Wyvern's Winter's Curse, Magnus's Reverse Polarity.
Beastmaster
*
False Promise effectively nullifies Primal Roar's single-target initiation on allies.
Purifying Flames kills Beastmaster's Hawk instantly and Boar with two casts.
*
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.
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.
*
*
Additional:
* Fortune's End can dispel