* Unlike other illusion heroes, Tempest Double won't be instantly destroyed by Stone Gaze since it is considered a clone and not an illusion.
* He can use either his own or his double's Flux to bypass the spellblock from Linken's Sphere, using the leftover Flux + Spark Wraith to slow Medusa's move speed to a crawl.
* Arc Warden has a farming advantage with double Hand of Midas, and can generally bully Medusa with other items that benefit from duplication.

* Arc Warden's Flux tears through Refraction charges almost instantly. Should he have a Tempest Double and no creeps are around, a 75% slow means almost certain death.
* Meld is useless against Spark Wraith.
Additional:
* Flux wastes Templar Assassin's Refraction unless she has a Black King Bar or a Manta Style.
* Spark Wraith can be used to bully a Templar Assassin that used Meld.

* Pugna's Decrepify can render Templar Assassin's physical attacks useless.
* Pugna can also cast Life Drain on Templar Assassin, burning her Refraction instances.
* On the other hand, Pugna generally has low health and armor. Use this to your advantage.

* Nether Ward will cause an unfriendly area for Medusa, draining her mana.

* Phantom Lancer with Diffusal Blade will very quickly burn Medusa's mana, making Mana Shield significantly less effective.
* Doppelganger's 1 second invulnerability can be used to dodge Medusa's petrification from Stone Gaze, as well as Mystic Snake.
* Phantom Lancer's illusions outnumber Medusa's targets from Split Shot, likely shielding your team in the process.

* Phantom Lancer's illusions destroy Refraction charges very quickly.

* He won't be around waiting for Medusa to Stone Gaze and pin him until she bears a true sight.
* With Smoke Screen, Riki will silence and catch Medusa in a surprise with high miss chance flushing her from positions easily in team fights.
* He can still deal huge amount of damage through Cloak and Dagger via backstabs, drying out Medusa's protection in a whim at random occassions.

* Because Templar Assassin does not have escape potential in lane, any support hero with roaming potential and a Dust of Appearance can be great at shutting her down early game: Earth Spirit, Spirit Breaker, Tusk, Bounty Hunter, Riki, Warlock.

* Blade Fury's damage over time dispels Refraction almost instantly.
* Juggernaut's high armor allows him to survive for long enough to remove Refraction and threaten her with Omnislash as long as he or his team carries detection.
* Templar Assassin's short attack range makes it difficult for her to target a well-placed healing ward. She cannot splash onto it with Psi Blades.

* Heroes that build Diffusal Blade or can fit it well into their item build will also make Medusa much less tanky: Riki, Naga Siren, Terrorblade, Juggernaut, Spectre, Slark,Drow Ranger.

* Medusa cannot chase Slark in any way and has no disable beyond her ultimate, making her unable to stop him getting away and regenerating before coming back to finish her off.
* Essence Shift removes 1 of every attribute, lowering Medusa's mana pool's cap and leaving her much more vulnerable in prolonged fights.
Additional:
* Medusa is especially vulnerable to Essence Shift, as both strength and intelligence contribute to her effective HP, while agility contributes to her damage.
* Dark Pact when timed right can be used to dispel Stone Gaze right after it petrifies Slark, allowing him to keep attacking Medusa throughout the duration.

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

Additional:
* Dark Pact rips through Refraction charges and still steals attributes during Refraction.
* Pounce and Dark Pact will still hit Templar Assassin while she is Melded. Since she cannot move, both abilities will be easy for Slark to land.

* Heroes that build Diffusal Blade or can fit it well into their item build will also make Medusa much less tanky: Riki, Naga Siren, Terrorblade, Juggernaut, Spectre, Slark,Drow Ranger.

* 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.
* 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), Pugna

Additional:
* Ensnare disables Lanaya's invisibility and Blink Dagger (a core item on Templar Assassin), and her illusions will break Refraction easily.

* Terrorblade is one of the strongest carries in the late game, due to his resilience against physical damage, which can be a problem for almost every strong burst physical damage carries, such as Phantom Assassin and Templar Assassin.

* Heroes that build Diffusal Blade or can fit it well into their item build will also make Medusa much less tanky: Riki, Naga Siren, Terrorblade, Juggernaut, Spectre, Slark,Drow Ranger.

* Webbed areas can be used to hit and run, covering distance hastily weakening her on the way and initiating ganks.
* Even though Medusa can hunt down Spiderlings easily when given enough range, after an Incapacitating Bite she will get her swarmed in no time.
* Medusa usual do not build a BKB to benefit from Mana Shield fully while Broodmother can fit a Diffusal Blade to burn away mana.
Additional:
* Incapacitating Bite will give Medusa a dire time to clear horde of small spiderlings or retaliate Broodmother herself.
* Spin Web will allow broodmother to pick her own fights and sometimes slip away to ambush Medusa.

* With her passive Split Shot, Medusa can be easily interrupted by Spiked Carapace during combat, especially during her precious Stone Gaze.
* Mana Burn quickly destroys Mana Shield, especially if Medusa only increases her mana pool by bolstering intelligence (which has the added bonus of increasing Mana Burn's damage).
* Uncontrollable damage from Mystic Snake and Split Shot can trigger Spiked Carapace.
* Medusa lacks single target damage, making a Burrowed Nyx Assassin hard to kill.
Additional:
* Level 4 Mana Burn burns 38,5% of Medusa's mana every 4 seconds if Medusa only increases her mana pool with intelligence. Additionally, 60% of the Mana Burn damage gets mitigated by Mana Shield, burning even more mana.
* Due to the passive nature of Mystic Snake and Split Shot, it can possibly proc Nyx's Spiked Carapace if he's within range of Medusa's abilities and isn't invisible.
* Medusa lacks single target damage, making Nyx with Aghanim's Scepter extremely hard to deal with if Medusa is the team's main damage source.

* The damage block instances of Refraction can be burned down with Ignite.

* Razor's Eye of the Storm damage-over-time easily wear off Refraction charges, allowing Templar Assassin to be damaged.
* Static Link empties Templar Assassin's damage output even with the bonus from Refraction, and will keep doing that even if the Razor cannot see her during Meld.
* Plasma Field can easily strike her during Meld.

* Shackles and Mass Serpent Ward instantly destroy Refraction

* Sand King can quickly remove her Refraction with his Sand Storm.
* Once Refraction is down, she is very vulnerable to Epicenter's high magic damage.

* Ion Shell destroys Refraction's protection stacks in short time.
* Surge ignores the massive slow from Psionic Trap.

* Fiend's Grip provides mana drain, which can heavily damage Mana Shield and prevent Medusa from using Stone Gaze.
* Even if she does use Stone Gaze, Nightmare can buy enough time to protect allies and reset the fight.
Additional:
* His Fiend's Grip will leave Medusa defenseless after he's done, if his teammates can provide cover for him or he initiates at the right time by Spell immunity.

* Icarus Dive allows Phoenix to shrug off the slow from her trap and make an easy escape from her ambush.
* As Templar Assassin relies on her quality-over-quantity bursting attacks to make quick work on fragile target, Fire Spirits' attack speed reduction can cripple her ability to deals any damage during combat. With the debuff applied in early-mid game, a Meld-breaking hit from her is significantly slowed to the point that her target can make a safe distance before she even landed the hit.
* Sun Ray has quick damage tick and will burn through her Refraction in no time.
* Supernova deals damage over time in an incredibly large area, and again with her quality-over-quantity style, she may not be able to attack quickly enough to break through the Phoenix Sun by herself. (not to mention the debuff from Fire Spirits) This can lead to a failed ganking attempt or even a turnaround.
Additional:
* Her Refraction charges can and will be easily burned away by Phoenix's damage over time abilities, and Meld can't protect her from Phoenix's AoE abilities, even without detection.

* Windranger's Focus Fire tears apart Templar Assassin's refraction very quickly and easily bursts here down due to her low health pool against Windranger's immense attack speed
* Templar Assassin's "Psionic Trap" doesn't slow down Windranger due to her skill Windrun
* Templar Assassin's high damage can also be easily evaded thanks to Windrun's 100% evasion
Additional:
* Venomous Gale and Plague Wards allow to quickly melt through Refraction charges.
* Both Poison Nova and Venomous Gale hit invisible units, so Meld cannot be used defensively.

* Despite the armor reduction from Meld, Templar Assassin's reliance on physical damage and medium attack speed is unlikely to harm Dragon Knight.
* Templar Assassin's Refraction charges also get quickly removed by the damage over time from Dragon Knight's ultimate.
Additional:
* The damage over time from Dragon Knight's Elder Dragon Form rapidly burns down Refraction, allowing him to attack her. Also, Breathe Fire reduces Templar Assassin's damage and Dragon Tail is a stun with a considerable duration, letting him and his team whittle her health down once her defenses wear off.

* All of Jakiro's active skills can be targeted on an area, which is effective at forcing Templar Assassin to move should she Meld away.
* Many of Jakiro's spells utilize damage-over-time mechanics, which makes it easy to strip away layers of Refraction.

* 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.

* Windranger's Focus Fire tears apart Templar Assassin's refraction very quickly and easily bursts here down due to her low health pool against Windranger's immense attack speed
* Templar Assassin's "Psionic Trap" doesn't slow down Windranger due to her skill Windrun
* Templar Assassin's high damage can also be easily evaded thanks to Windrun's 100% evasion

* Huskar's burn damage from Burning Spear is incredibly strong against Templar Assassin as it completely cancels out her Refraction from the burning over time which results in making her very vulnerable to being ganked or harassed, and in turn forcing her out of the lane.

* Medusa lacks mobility or escape mechanisms. Earth Spike and Hex can neutralize her strong damage potential and allow for Lion's team to focus her down.
* In addition to easily breaking her commonly bought Linken's Sphere with its low cooldown, Mana Drain can quickly drain her Mana Shield, making her far less tanky.

* The damage over time from Viper's Poison Attack and Viper Strike rapidly wear down Refraction charges, allowing Templar Assassin to be damaged. Additionally, Corrosive Skin causes her attacks to apply damage over time on her as well.
* Nethertoxin is a big threat to Templar Assassin. Her initially low range making it very hard to deal against Nethertoxin in laning phase. At any stage of the game, a Nethertoxin can always force her to undo her Meld.
Additional:
* All of Viper's abilities quickly burn through Refraction charges.
* Templar Assassin's short range, aside from Psi Blades' spill damage, makes her vulnerable to Poison Attack harassment.
* Templar Assassin traditionally forgoes health and armor items for damage. Outside of Black King Bar, Viper will almost always be able to kill her when Refraction is down.

* His Rot can force Templar Assassin out of her Meld and destroy all of her Refraction charges quickly, and her small health pool and meager defense make her very vulnerable to his Meat Hook without Refraction.

* Batrider's abilities are designed to deal damage over time, burning through Templar Assassin's layers extremely quickly. Flamebreak applies 7 instances of damage, burning through the entirety of Refraction, and Firefly applies damage on the place, forcing her to either get out of Meld and be attacked or stay in place or be incinerated.
Additional:
* Batrider's DoT damage quickly removes Templar Assassin's Refraction and can damage her during Meld.

* Because of her need to get status items early to tank it up, Rubick can greatly reduce her damage early with Fade Bolt
* Her stationary nature and the slow cast time of her spells makes it easier for Rubick to steal Stone Gaze or Mystic Snake
* Aghanim's Scepter's Mystic Snake is often better used by Rubick than by Medusa

* Other heroes who has armor and slow debuffs won't allow Medusa to disengage from combat: Tidehunter, Bristleback, Slardar.

* Because Templar Assassin does not have escape potential in lane, any support hero with roaming potential and a Dust of Appearance can be great at shutting her down early game: Earth Spirit, Spirit Breaker, Tusk, Bounty Hunter, Riki, Warlock.

* Other heroes with mana burning or manipulating abilities will make Medusa much less tanky: Lion, Mirana, Weaver.

* 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.
* 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), Pugna

* Heroes that have disposable area-targeted spells can force her to undo her Meld: Leshrac, Puck, Tiny. An experienced Templar Assassin could try to Refraction before Meld so she can tank through those damage without getting her Blink disabled.

* Other heroes with mana burning or manipulating abilities will make Medusa much less tanky: Lion, Mirana, Weaver.

* Because Templar Assassin does not have escape potential in lane, any support hero with roaming potential and a Dust of Appearance can be great at shutting her down early game: Earth Spirit, Spirit Breaker, Tusk, Bounty Hunter, Riki, Warlock.

Additional:
* Templar Assassin is dependant on Refraction in teamfights. Because Magnetize deals damage per second and Earth Spirit is even able to refresh the duration of his ultimate he is suitable for wasting Refraction and allowing his team to take her down.

* Because Templar Assassin does not have escape potential in lane, any support hero with roaming potential and a Dust of Appearance can be great at shutting her down early game: Earth Spirit, Spirit Breaker, Tusk, Bounty Hunter, Riki, Warlock.

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

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

* Heroes who can provide True Sight are always credible threats: Slardar, Bounty Hunter, especially Zeus since his Lightning Bolt provides True Sight without the need to detect her beforehand to apply the debuff. So even a late-coming Zeus can easily scout a large area to reveal her, and she cannot purge herself from his sight with the dispel talent.

* Other heroes who has armor and slow debuffs won't allow Medusa to disengage from combat: Tidehunter, Bristleback, Slardar.

* Other heroes who has armor and slow debuffs won't allow Medusa to disengage from combat: Tidehunter, Bristleback, Slardar.

* Attacks from Boars and the attack speed boost from Inner Beast will quickly wear down Refraction.
* True Sight provided by Level 3 Necronomicon can see Templar Assassin in Meld.

* Firestorm will destroy Refraction charges very quickly.
* Firestorm will hit Templar Assassin while Melded.
* Templar Assassin has a hard time maneuvering around Pit of Malice.

* As with other heroes mentioned in this section, Templar Assassin is not a hero that is fully "countered" by Crystal Maiden (the way she is against Viper and Jakiro), however, the proper combination and execution Crystal Maiden's spells, stacked with her team, can most certainly spell the end for Templar Assassin.
* Frostbite can quickly eat away Refraction charges, leaving Templar Assassin vulnerable for the rest of her team to kill.
* Freezing Field will still apply damage to Templar Assassin when she is under the effect of Meld, making it an even less viable form of escape until a Blink Dagger is purchased.
* Blink Dagger is also cancelled by all of Crystal Maiden's spells, and the fairly short cooldowns on Frostbite and Crystal Nova make her a great asset to a chase against Templar Assassin.
* This is not to say that Templar Assassin has any difficulty killing off the low armor, low HP pool Crystal Maiden, so fighting her alone is never advised.

* Medusa's tankiness doesn't help her very much against Fury Swipes in long teamfights.
* With no escape mechanism and a slow movement speed, getting jumped on by Ursa usually spells a quick end for Medusa in the early game.
Additional:
* Ursa's status resistance from Enrage will ignore Medusa's gaze.
* Ursa can stack damage with Fury Swipes easily against her Mana Shield in a prolonged team match.

* Silencer burns easily through her effective hp from Mana Shield, by taking away her int.
* Arcane Curse punishes her repeatedly casting Mystic Snake to keep her mana pool high. Can force her to use Manta Style before he has cast Global Silence and Medusa usually does not want to build Black King Bar.

* Medusa is a fairly immobile hero that deals damage around her with Split Shot. Sniper should outrange her and should stay out of harm's way from Split Shot.
* More importantly, Sniper should have enough attack range to fire at Medusa during her Stone Gaze without turning to stone, so the ultimate is mostly wasted against him.
Additional:
* Sniper can outrange both Medusa's arrows and Stone Gaze, allowing him to focus her down during a teamfight.

* Chakra Magic can drain her current mana, draining away her effective health in a sneaky way.
* Will-O-Wisp will keep Medusa busy after she got hit by Blinding Light.