* Mana Drain depletes Nercophos's mana pool, preventing him from using his abilities.
* Finger of Death deals high magical damage, which becomes amplified by Ghost Shroud.

* Mana Shield tanks 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.

* If Meepo ganks Lion with Poof and Earthbind, he will be an easy target for Earth Spike & AoE Hex from his level 25 talent.

* 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 nukes: Bane, Lich, Lion, Skywrath Mage

Additional:
* Enchantress is very fragile without any form of magic resistance, allowing Lion to easily burst her down.
* Nature's Attendants is a slow heal, making it ineffective against Lion's burst.
* Enchantress lacks any escape mechanism apart from her raw movement speed, allowing Lion to disable her.
* Since Lion's damage comes mostly from his skills, Untouchable does nothing to mitigate it.

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

* Despite her high mobility, Hex or Earth Spike can lock Phantom Assassin down and make her vulnerable.
* Although she has high evasion through Blur, Phantom Assassin has a rather low health pool, making her weak to Lion's magical burst.

* 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.

* Sven is very vulnerable to chain stun such as Lion, Shadow Shaman or Magnus.

* 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 manfight Medusa at any stage of the game.
* Mystic Snake can slow Sven down enough for allies to capitalise on his commitment in a fight.

* Mana Drain has an extremely long range and low cooldown. It can easily deplete most heroes of their entire mana pools, especially those with smaller mana pools such as Tiny or Spirit Breaker.

* If Medusa activates Stone Gaze, the charge will inevitably fail.
* Mana Shield and overall tankiness allows Medusa to easily survive Spirit Breaker's initiation.

* Ranged heroes that can easily harass Axe: Drow Ranger, Sniper, Lion.

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

* Enigma is fragile, and lacks escapes, being dependent on Blink Dagger for mobility. Ganking Heroes or Heroes with burst damage will likely kill him before he can do anything. Such Heroes include: Lina, Lion, Luna, Puck, Slark, Nyx Assassin, etc.

* 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.

* Both Hex and Mana Drain destroy Naga Siren's illusions in an instant, making it hard to teamfight or push against a team with Lion. If Lion chooses the AoE effect talent for Hex or the shard for multi-target Mana Drain, it can negate her pushing potential entirely.
* Earth Spike is an AoE disable with good damage. If used well, it can help distinguish the true Naga Siren by the damage they take (illusions take more damage).

* Medusa's Split Shot will whittle down all of Naga Siren's illusions, including Naga Siren herself.

* Heroes with channeling spells, for Chen has no disables on his own, hates buying disabling items and his creeps are often not fast enough to cancel them: Enigma's Black Hole, Witch Doctor's Death Ward, Shadow Shaman's Shackles, Lion's Mana Drain, Bane's Fiend's Grip, Pudge's Dismember, Crystal Maiden's Freezing Field, Pugna's Life Drain, Dawnbreaker's Solar Guardian, and Naga Siren's Reel In from Aghanim's Scepter.

* Heroes with strong area-of-effect damage can make quick work of Chen's converted creeps and at same time gain farm: Magnus, Jakiro, Shadow Fiend, Kunkka, Luna, Dragon Knight, Medusa, Alchemist.

* Mana Drain rapidly saps Morphling's already low mana pool, making him unable to use Waveform or Adaptive Strike. Additionally, Hex prevents these abilities as well.
* An Earth Spike and Finger of Death combo can burst an unwary Morphling down if he has his strength fully shifted to agility.

* Hex greatly reduces Timbersaw's mobility.
* In addition, Lion can follow up with his Earth Spike and Mana Drain combo, preventing Timbersaw to escape with Timber Chain. And he can finish Timbersaw off with Finger of Death if the latter's HP is low enough.

* 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.

* All of Lion's abilities are active making Demonic Purge break from Aghanim's Scepter useless.
* Hex and Mana Drain can make quick work of whatever illusions you're creating, especially when he acquires his Talents at level 20 and 25.
* An attempt to save an ally using Disruption can easily become a perfect setup for a Earth Spike or Finger of Death with Aghanim's Scepter for the enemy.

* 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.

* Lion possesses two strong disables in Earth Spike and Hex and heavy magic burst with Finger of Death which help lock him down and prevent him from escaping with Activate Fire Remnant. When getting his Blink Dagger Lion can punish Ember Spirit's overextension immediately, or initiate a fight on him with disables.
Additional:
* Ember lacks any protection against Lion's disables early in the game and often does not acquire any later, allowing Lion to Hex or Earth Spike him before he escapes through his Fire Remnant.
* Although Flame Guard can prevent magic damage, it does not stop Lion's disables, and Lion can usually break through it with Finger of Death.

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

* Although Weaver can potentially Time Lapse out of any burst, Weaver has a fragile health pool, and Lion's disables can kill him before.
* Weaver is very mana dependent and has a rather small mana pool in the beginning of the game. Mana Drain can deplete him of mana and lessen his early game presence.
* Earth Spike can be point targeted and hits through Shukuchi to make him vulnerable.
* Linken's Sphere is easily broken by targeted spells with low cooldown.

* With a lot of disables with good range, he might cancel your Echo Stomp.
* Mana Drain can be used to drain Elder Titan's already low mana pool.

* Heroes with long or multiple disables will prevent Legion Commander from winning Duels: Shadow Shaman, Lion

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

* Hex and Earth Spike can hold Clinkz down, giving him no chance to use Black King Bar or Skeleton Walk.
* Finger of Death quickly kills Clinkz due to his low health.

* 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.

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

* 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

* High priority targets like Queen of Pain, Drow Ranger and even Anti-Mage can't get caught out from Lion's long range disables.

* One of Lion's level 20 talents lets Mana Drain affect 2 secondary targets. This can make things difficult for heroes like Phantom Lancer, Chaos Knight, and Terrorblade who rely on illusion armies.
* Mana Drain and Hex instantly kill any illusions. Finger of Death upgraded with Aghanim's Scepter also shreds most illusions.
* One of Lion's level 20 talents lets Mana Drain affect 2 secondary targets. This can make things difficult for heroes like Phantom Lancer, Chaos Knight, and Terrorblade who rely on illusion armies.

* Heroes that can keep Marci for a long time in one place so she can't pursue her targets, like Bane, Lion, Shadow Shaman, Invoker, Disruptor and Kunkka.

* Heroes with high burst damage: Lina, Lion, Luna, Nyx Assassin, Queen of Pain.

* Heroes with forced movement abilities or non-interrupting forced movement, such as Lion, Drow Ranger, Magnus, Mars, as they can cancel blast-off mid air, removing his ability to initiate or escape.

* Since Windranger is bad against magical damage, heroes with continuous magical damage or magical nukes can blast her: Zeus, Tinker, Leshrac, Viper, Skywrath Mage, Lion, Lina, Venomancer.

* Heroes with mana burn: Nyx Assassin, Invoker, Outworld Destroyer, Pugna, Lion

* Heroes that can drain mana negatively affect Viper's ability to use Poison Attack, Nethertoxin and Viper Strike: Lion, Anti-Mage

* Lion's disables are also really effective against channeling Heroes, like Enigma or Crystal Maiden.

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

* Heroes with silence and mana drain abilites, as Ancient Apparition relies entirely on his abilities: Invoker, Silencer, Nyx Assassin, Skywrath Mage, Shadow Shaman, Lion and etc.

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

* Due to her slow movement speed,heroes with crowd control and slows can shut down Dawnbreaker. ( Lion, Crystal Maiden ,Venomancer etc.)

* Heroes with high magical burst damage will kill Gyrocopter before he gets to do much: Lina, Lion, Zeus

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

* Finger of Death can instantly shred many targets especially fragile Heroes like Keeper of the Light, Ancient Apparition, or Bounty Hunter.

* Heroes with high burst damage through their physical attacks or spells can kill Dazzle or his allies before he has a chance to use Shallow Grave. (Lina, Lion, etc.)

* Heroes with high magical burst can easily kill Huskar when he is at low health: Lion, Lina, Skywrath Mage

* Heroes that can kill Death Prophet with nukes can prevent her from using Exorcism to its full duration or using it at all: Lina, Lion, Puck, Morphling.

* Heroes who can drain mana can make Omniknight useless after he uses one or two abilities: Lion, Anti-Mage, Nyx Assassin.

* Mana Drain is a headache for Bristleback to deal with during the laning stage, as it denies him the ability to get last hits with Quill Spray.
* Finger of Death deals high damage to Bristleback, and only triggers his passive once.

* Lion's instant cast point shuts down his initiation and buys time for his allies to catch up.
* Void Spirit has to be cautious when fighting,as he has no protection against Finger of Death.If caught out in a stun,the high magic damage could end him quickly.

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

* 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 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.

* Drow has a very low health pool, allowing Lion to burst her down.
* Drow has no innate escape mechanism, making her an easy target for Lion's disables.
* Lion should be wary of Drow's Gust however, as he has no natural means to deal with it.

* Hex and Mana Drain can be used to immediately destroy Spectre's illusion when she Haunts. A fast fingered Lion can protect himself and a teammate.
* Hex and Earth Spike are good lockdown spells to control and kill Spectre, especially if she doesn't buy defensive items like Linken's Sphere and Black King Bar.
* Finger of Death can be used to burst down Spectre when she is low on life as she has very poor magic resistance.

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

* One of Lion's level 20 talents lets Mana Drain affect 2 secondary targets. This can make things difficult for heroes like Phantom Lancer, Chaos Knight, and Terrorblade who rely on illusion armies.
* Mana Drain and Hex instantly kill any illusions. Finger of Death upgraded with Aghanim's Scepter also shreds most illusions.
* One of Lion's level 20 talents lets Mana Drain affect 2 secondary targets. This can make things difficult for heroes like Phantom Lancer, Chaos Knight, and Terrorblade who rely on illusion armies.

* Mana Drain has an extremely long range and low cooldown. It can easily deplete most heroes of their entire mana pools, especially those with smaller mana pools such as Tiny or Spirit Breaker.

Additional:
* Lion can continuously Mana Drain Tiny in the early game, depleting his small mana pool for his abilities.

* Wraith King has a very low mana pool and depends on it to cast Reincarnation. Mana Drain will render him useless.
* Wraith King has very low mobility, making it easy for Lion to disable and harass him.
Additional:
* While not being able to confront Wraith King by himself, Lion's Mana Drain helps in draining Wraith King's mana, preventing him from reincarnating unless he has his Aghanim's Shard.
* Lion's Earth Spike and Hex provide decent lockdown against Wraith King as well, preventing the latter from benefiting from Vampiric Spirit bonuses.

* Mana Drain is very effective against heroes that have mana burn abilities such as Anti-Mage, Nyx Assassin and Keeper of the Light.

* Like above, supports with reliable stuns can be a massive problem and force Black King Bar in fights unideally, such as Shadow Shaman, Lion, Nyx Assassin.

* 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.

* Heroes with long disables, like Lion, Night Stalker, or Legion Commander, can prevent Oracle from using spells or items.

* Lion has two low cast point disables (Hex and Earth Spike) to control Ursa before he buys a Black King Bar.
* Hex is one of the few abilities that cannot be dispelled even with an Aghanim's Scepter upgraded Enrage.
* Lion can control Ursa's low mana pool via Mana Drain.

* Heroes with silences and hard stuns such as Doom, Silencer, and Lion can keep Mirana from Leaping away.