* Attacks from Boars and the attack speed boost from Inner Beast will quickly wear down Refraction.

* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Jakiro, Pugna
* 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

* Primal Roar takes Sven out of the fight completely, even with Black King Bar.

* Heroes that relies on armor or other type of physical damage negation are easy for Gyrocopter to take down during the early game with his magical damage: Axe, Dragon Knight, Sven.

* 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.

* Flak Cannon and Call Down will shred Meepo's clones.
* Homing Missile can catch and single out retreating Meepos, making them an easy kill.

* Heroes with disables that ignore spell immunity will render Phantom Assassin quite useless in teamfights throughout the game: Axe, Enigma, Vengeful Spirit, Doom, Bane, Beastmaster, Pudge, Medusa.

* Heroes with heavy early and mid-game magical damage are also problematic for Phantom Assassin due to being able to easily kill her before she gains an item advantage: Lina, Necrophos, Nyx Assassin, Gyrocopter. Should be noted these heroes are usually quite squishy and don't scale well with health. So to some respect, they are on a time crunch.

* Flak Cannon destroys Terrorblade's illusions very quickly.

* 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.

* Wild Axes destroys large amounts of trees specially upgraded with Aghanim's Scepter,

* Primal Roar and the slow from Boars make kiting Tiny very easy.

* Wraith King's lack of area of effect spells makes him easily overwhelmed by Beastmaster's summons.

* Primal Roar and the slow from Boars make kiting Troll Warlord very easy.

* Flak Cannon destroys Phantom Lancer's illusions very quickly.
Additional:
* Flak Cannon and Call Down destroy Phantom Lancer's illusions very quickly.

* Inner Beast helps Beastmaster's team destroy Supernova quickly.

* Flak Cannon and Call Down can easily clear Naga Siren's illusions.

* Primal Roar and the slow from Boars makes kiting Ursa very easy.

* Flak Cannon rips through Tombstone's zombies.
Additional:
* Flak Cannon enables Gyrocopter to clear the zombies easily.

* Primal Roar allows Beastmaster to keep Lycan in place after he used his Shapeshift.

* Heroes that relies on armor or other type of physical damage negation are easy for Gyrocopter to take down during the early game with his magical damage: Axe, Dragon Knight, Sven.

* Heroes with disables that go through spell immunity can end Bloodseeker before he has the chance to do anything: Batrider, Beastmaster

* Illusion or summon-based heroes can be a problem to Viper due to his lack of AoE damage: Naga Siren, Phantom Lancer, Beastmaster

* Heroes that relies on armor or other type of physical damage negation are easy for Gyrocopter to take down during the early game with his magical damage: Axe, Dragon Knight, Sven.

* Heroes who relies on illusions and summons (Beastmaster, Chaos Knight, etc.).

* 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'sMeat Hook.

* 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 cleave or multi-target attacks can quickly take on Familiars and reduce Visage's firepower like Gyrocopter, Kunkka, Magnus and Medusa.

* Flak Cannon destroys Chaos Knight's illusions very quickly.

* Beastmaster's Hawk can find Tinker easily while he is pushing or blinking into trees.

* 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

* Heroes who rely on high mobility are especially vulnerable to Primal Roar: Storm Spirit, Ember Spirit, Queen of Pain.

* Heroes with illusions and summons can manfight Night Stalker: Terrorblade, Beastmaster, Broodmother.