* Medusa cares less than other heroes about armor reduction, since Mana Shield blocks 70% of all damage without taking armor/magic resistance into consideration. This makes 60% of your Corrosive Haze ineffective until Medusa's mana is drained.

* Medusa's Stone Gaze forces Mars to choose between getting petrified, or turning his vulnerable back on Medusa.

* Heroes with a lot of burst damage, especially those who rely on casting spells: Lina, Zeus.

* Clinkz, Sniper, Lone Druid, Troll Warlord, Legion Commander and Wraith King are some of the Heroes that base themselves on attacks with little or no spell power, so they suffer in the grassy hands of Overgrowth.

* Heroes that can maintain vision on Monkey King can see when he uses Tree Dance: Bloodseeker, Treant Protector with Eyes In The Forest, Sniper, Weaver

* Nature's Grasp severely slows down Spirit Breaker, reducing effects of Charge of Darkness and Greater Bash.
* Living Armor can mitigate a large portion of Spirit Breaker's damage since his attacks are slow.
* Treant Protector can also counter-initiate against Spirit Breaker with Leech Seed, Overgrowth and with his root from {I|Aghanim's Shard
* Aghanim's Scepter gives Treant Protector access to Eyes In The Forest ability, which allows him to turn trees into wards that provide vision, allowing him to keep his allies warned about Spirit Breaker's attempts to gank them. Eyes In The Forest will also trigger Overgrowth if Spirit Breaker is in range of the tree affected by it.
Additional:
* Spirit Breaker's slow attacks cannot harm a hero shielded by Living Armor.

* If Medusa activates Stone Gaze before Spirit Breaker reaches her with Charge of Darkness, the charge will inevitably fail.
* Medusa has three ways to counter Spirit Breaker's Charge of Darkness: Stone Gaze can disable Spirit Breaker's Charge of Darkness if he faces Medusa directly. Aghanim's Scepter upgraded Mystic Snake can disable Spirit Breaker and cancel his Charge of Darkness if it hits him. And Cold Blooded provided by Aghanim's Shard that can cast a single-targeted Mystic Snake at Spirit Breaker if he uses Charge of Darkness on her.
* Mana Shield and overall tankiness allows Medusa to easily survive Spirit Breaker's initiation. And to make things worse, Spirit Breaker is not a common Diffusal Blade nor Disperser wielder to counter this problem at all.
* Overall, any attempt for Spirit Breaker to gank and kill Medusa will hurt him more than the other way around.

* Heroes with powerful rooting abilities will disable most of Pangolier's skills, a bonus point if it pierces spell immunity since it will also be able to stop Pangolier during his Rolling Thunder: Treant Protector, Meepo, Crystal Maiden, Dark Willow, Underlord, Naga Siren

* Split Shot will keep attacking Pangolier even when he is rolling around.
* Stone Gaze stuns Pangolier during Rolling Thunder, or forces him to roll away.

* Overgrowth prevents Phantom Assassin from using Blink Strike even through her spell immunity.
* Living Armor reduces Phantom Assassin's physical damage whenever she attempts to gank an allied hero.

* 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, Warlock.

* Treant Protector can usually scout out Magnus in the trees with Eyes in the Forest and disrupt his initiation attempts. He can also counter Magnus' initiation with Overgrowth.

* Any hero who can counter-initiate in anticipation without getting caught in Reverse Polarity: Sven, Omniknight, Enigma, Luna, Naga Siren, Mars, Jakiro, Venomancer, Elder Titan, Faceless Void, Rubick, Keeper of the Light, Pugna, Invoker, Spectre, Alchemist, Treant Protector, Lina, Oracle, Zeus, Shadow Shaman, Phoenix, Razor, Huskar, Batrider, Kunkka, Tidehunter, Wraith King, Sand King, Medusa, Dawnbreaker.

* Heroes with global abilities can give Legion Commander's opponent an edge in Duels from anywhere on the map: Nature's Prophet, Ancient Apparition, Zeus, Invoker, Treant Protector

* Mana Shield makes Medusa very hard to take down in Duels.
* Stone Gaze stops Legion Commander from Dueling altogether, regardless of who she targets.

* Treant Protector grants protection against his attacks with Living Armor and his ultimate, Overgrowth is a massive AoE disarm and root that pierces spell immunity, causing trouble to Lycan. You will find yourself in need of an ally's dispel or forced to pop Black King Bar for its dispel.

Additional:
* Lycan has no kind of teleport, being only able to walk, and heavily relies on his attacks. As Overgrowth roots and disarms the targets, Lycan can't do much in an overgrowth field.

* Her Mana Shield is too tough for Lycan to break.
* Mystic Snake can hit for a massive damage once it spread between his summons.
Additional:
* Can be easily petrified despite his speed.
* Summoned wolves will be targeted by Split Shot or Mystic Snake

* Enchantress often has a small army of neutral creeps, allowing Medusa to hit her with a later bounce of her Mystic Snake.

* Doom does not disable Mana Shield. As such, Doom's damage is largely mitigated by her mana shield. Additionally, Medusa is not reliant on her abilities to be effective during a teamfight, making Medusa an unproductive hero to target.
* Medusa is an ideal Linken's Sphere carrier. Should one be purchased, and without any additional disables, Doom may find that few opportunities exist to effectively lockdown, disable, and kill Medusa.

* Stone Gaze allows Medusa to easily kite and kill Sven.
* Mana Shield negates much of Sven's burst damage.
Additional:
* Mana Shield makes it very hard for Sven to burst her within Storm Hammer's stun duration.
* Stone Gaze makes it very difficult for Sven to fight Medusa at any stage of the game.
* Mystic Snake can slow Sven down enough for allies to capitalize on his commitment in a fight.

* If Storm Spirit is caught in an Overgrowth, he is shut down.
* With the exception of Electric Vortex, he won't be able to cast any relevant skill.

* Another hero heavily based on attacks and no mobility, being an easy prey for Treant strong disarms and motion reduction skills.

* Treant can give chase should Hoodwink attempt to Scurry away, and Nature's Grasp can slow her down so Treant Protector's teammates can pin Hoodwink down.

* Split Shot can destroy Tombstone Zombies and Tombstone itself while still damaging heroes.

* Should Luna choose to buy Manta Style, Medusa will be able to kill illusions from them with Split Shot and Mjollnir, which is a common item on Medusa.
* Mystic Snake allows Medusa to easily harass Luna and steal mana from her, preventing Luna from retaliating with Lucent Beam.
* Medusa can survive Eclipse thanks to Mana Shield, which can cause Luna to struggle greatly in bursting down Medusa and force her to buy Diffusal Blade and it's upgrade Disperser.
* Even with Black King Bar, Medusa's Stone Gaze will still be able to disable Luna, which could even discourage her from counter-initiating with Eclipse.
* For the same reasons, Medusa makes a very powerful ally for Luna when they are in the same team.
Additional:
* Should Luna choose to buy Manta Style, Medusa will be able to kill illusions from them with Split Shot and Mjollnir, which is a common item on Medusa.
* Mystic Snake allows Medusa to easily harass Luna and steal mana from her, preventing Luna from retaliating with Lucent Beam.
* Medusa can survive Eclipse thanks to Mana Shield, and since Luna is not a hero that often goes for Diffusal Blade, she will struggle greatly in bursting down Medusa.
* Even with Black King Bar, Medusa's Stone Gaze will still be able to disable Luna, which could even discourage her from counter-initiating with Eclipse.
* For the same reasons, Medusa makes a very powerful ally for Luna when they are in the same team.

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

* Mana Shield can tank most of the damage from Reaper's Scythe; with sufficient mana, the kill threshold drops significantly.
* Necrophos has a movement speed equal to Medusa, and is easy to chase down with a slowing item in Medusa's inventory.

* Clinkz will often roam the map alone, and Treant Protector's Nature's Guise allows him to set up kills with his allies on Clinkz from invisibility.
* Treant Protector's very high damage allowing him to trade hits or contest last hits with Clinkz, while Living Armor can be used to sustain the harass.
* Living Armor protects any of Treant's allies ganked by Clinkz.
* In teamfights, Treant Protector's Overgrowth can disarm Clinkz, preventing him from turning invisible and holding him in place even if he has a Black King Bar.
* Leech Seed slows Clinkz, preventing him from repositioning or fleeing away from danger.

* Living Armor can be used to save a hero from a Relocate gank.

* Medusa's Split Shot can easily kill Chen's creeps.
* Mystic Snake can quickly kill Chen's creeps and deal intense damage for every killed creep while also draining their mana with each bounce. Aghanim's Scepter upgraded Mystic Snake can also disable both, Chen and his creeps upon impact.
* Mana Shield will make it impossible for Chen to burst down Medusa.
* Stone Gaze can disable Chen from using Hand of God to save himself or his allies.

* Visage's familiars are easy targets to Split Shot.
* Mana Shield will resist Soul Assumption instances without effort.

* Poof won't damage Medusa and she can use Stone Gaze to disable all of Meepo's clones.
* Mystic Snake will easily become the bane of Meepo early game.

* Heroes with Linken's Sphere as core item: Weaver, Morphling, Medusa.

* In general, heroes that provide vision will see Fiend's Gate coming: Techies, Templar Assassin, Treant Protector

* Overgrowth has a great duration, which prevents the units caught from attacking, moving and Blinking. Heroes like Storm Spirit, Mirana, Anti-Mage and others won't be able to do much if they're caught.

* Clinkz, Sniper, Lone Druid, Troll Warlord, Legion Commander and Wraith King are some of the Heroes that base themselves on attacks with little or no spell power, so they suffer in the grassy hands of Overgrowth.

* Heroes with a lot of burst damage, especially those who rely on casting spells: Lina, Zeus.

* Clinkz, Sniper, Lone Druid, Troll Warlord, Legion Commander and Wraith King are some of the Heroes that base themselves on attacks with little or no spell power, so they suffer in the grassy hands of Overgrowth.

* Treant Protector's Living Armor will also negate Tidebringer's damage.

* Clinkz, Sniper, Lone Druid, Troll Warlord, Legion Commander and Wraith King are some of the Heroes that base themselves on attacks with little or no spell power, so they suffer in the grassy hands of Overgrowth.

* Medusa's Split Shot can make quick work of Enigma's Eidolons and take advantage of their considerable bounty.
* Medusa can also kill Eidolons with her Mystic Snake that can also greatly damage Enigma and drain some of his mana.
* If Medusa activates Stone Gaze at the start of a fight, it can make initiating and landing an effective Black Hole exceedingly difficult, because Stone Gaze can cancel Enigma's Black Hole even through spell immunity, which can discourage Enigma from even trying to initiate with Black Hole.
Additional:
* Medusa's Split Shot can make quick work of Enigma's Eidolons and take advantage of their considerable bounty.
* If Medusa activates Stone Gaze at the start of a fight, it can make initiating — and landing an effective Black Hole exceedingly difficult. Stone Gaze can cancel Enigma's Black Hole even through spell immunity, which can discourage Enigma from initiating with Black Hole.

* Mana Shield makes it very difficult for Bloodseeker to gain his Thirst bonuses.
* Rupture rarely kills Medusa through Mana Shield.

* Medusa's Split Shot and Mystic Snake combined with Mjollnir, a common item for Medusa, will whittle down all of Naga Siren's illusions, including Naga Siren herself.
* Medusa's Stone Gaze can disable Naga Siren even for the duration of Song of the Siren and even if Naga Siren is spell immune, discouraging Naga Siren from even trying to use Song of the Siren to save herself or counter-initiate against Medusa.
Additional:
* Medusa's Split Shot and Mystic Snake combined with Mjollnir, a common item for Medusa, will whittle down all of Naga Siren's illusions, including Naga Siren herself.
* Medusa's Stone Gaze can disable Naga Siren even for the duration of Song of the Siren and even if Naga Siren is spell immune, discouraging Naga Siren from even trying to use Song of the Siren to save herself or counter-initiate against Medusa.

* Heroes with abilities that can save teammates are also effective such as Shadow Demon, Dazzle, Oracle, Bane, Pugna, Tusk, Winter Wyvern, Io, Underlord, Treant Protector and Keeper of the Light.

* Mana Shield reduces the effectiveness of Counter Helix.
* Stone Gaze makes it very difficult for Axe to initiate on Medusa and her allies.

* Anti-Mage relies on blinking and attacking. Overgrowth prevents both.
* Be wary that he will eventually farm up a Manta Style that fully dispels Overgrowth. Good players will wait for your ultimate to use their manta. Perhaps an ally has a silence or similar that would force him to use his manta before your ultimate.