* Heroes that can easily bypass Io's allies to get to Io: Riki, Tusk, Clinkz, Sniper

* Due to his low health and armor, Riki can easily kill Skywrath Mage.
* Smoke Screen prevents Skywrath from using all of his abilities, as he does not tend to buy Black King Bar

* Fragile heroes: Bounty Hunter has decent nuking capabilities with Shiruken Toss and Jinada thus making fragile heroes easy picks for ganking. Few examples of such heroes are:Crystal Maiden, Pugna, Skywrath Mage, Io, Witch Doctor, etc.

* Fragile heroes: Bounty Hunter has decent nuking capabilities with Shiruken Toss and Jinada thus making fragile heroes easy picks for ganking. Few examples of such heroes are:Crystal Maiden, Pugna, Skywrath Mage, Io, Witch Doctor, etc.

* Skywrath mage also has a terrible time fighting against anything that isn't a hero. As Mystic Flare only affects heroes, 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 low armor and little mobility, like Huskar, Io, etc. will also have an unfortunate fate.

* Skywrath mage also has a terrible time fighting against anything that isn't a hero. As Mystic Flare only affects heroes, 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 that are hard to gank: Axe, Death Prophet, Phantom Lancer

* Thirst allows Bloodseeker to see where Io relocated to, should either Io or the tethered hero have low health.
* Rupture forces Io to stay in place, preventing it from using the Tether bonus movement speed to escape.

* Lightning Storm will usually hit both Io and its tethered target since both will be close enough for the lightning to jump.
* Diabolic Edict and Pulse Nova hit all units near Leshrac, meaning he can do colossal damage to Io and its tethered target.
Additional:
* Lightning Storm will usually hit both Io and his Tethered target since both will be close enough for the lightning to jump. It can then be followed up by Split Earth.
* Diabolic Edict and Pulse Nova hit all units near Leshrac, meaning he can do colossal damage to Io and his Tethered target.

* Ignite has long duration damage-over-time and prevents Io from healing his Tethered ally.

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

* Aphotic Shield removes silences, slows and stuns, possibly foiling a full-duration Mystic Flare.
* Borrowed Time makes it impossible to burst Abaddon down, even healing him up due to Mystic Flare's damage.

* Nether Ward will make Skywrath Mage next to useless in fights, as his low hp pool will not allow him to sustain through the damage of the ward should he choose to cast spells. Be wary though that Skywrath's huge burst will make very quick work of Pugna's low hp should the ward be destroyed, and Decrepify won't help you at all.
Additional:
* Due to the high mana cost of his spells and the low cool down of them, Nether Ward can seriously damage Skywrath Mage if he isn't careful.
* Skywrath Mage's fragility makes him very susceptible to Pugna's high burst damage.

* Skywrath Mage's low health makes him rather easy prey for Nyx Assassin and his lack of armor generally means he'll take the full brunt of a Vendetta strike.
* Mana Burn is annoying at all stages of the game as it turns Skywrath Mage's high intelligence growth against him.
* Spiked Carapace gives Nyx some degree of protection against Skywrath's spells.

* Charge of Darkness can be used to escape or counter-initiate against a Relocate gank.
* Greater Bash and Nether Strike is devastating due to Io's low armor, and can even knock it away from tethered target.

* Lucent Beam can cancel Tether and Relocate.
* Moon Glaives and Eclipse make short work of Io and its tethered ally.

* Lich's Chain Frost forces Io to give up providing buff to his ally with Tether or suffer devastating damage with his tethered ally.
* Lich could easily use Sinister Gaze to disable Io from getting away with Tether or Relocate.

* Glimpse directly negates Relocate.
Additional:
* Disruptor can always Glimpse back Io or his target after he Relocated nearby.
* Even better, thanks to the indicator on the ground, you can even preemptively drop Static Storm and Kinetic Field on the spot they will relocate to.
* Thunder Strike and Glimpse are also good tools to bring back an Io that Tethered away in the fog of war.

* Skywrath Mage's very low health allows Monkey King to ambush and finish him off quickly.

* In the early-mid game, Skywrath consistently needs to use his entire mana pool to kill a hero, but Wraith King's Reincarnation allows him to finish off Skywrath after the first death, as Skywrath Mage will have likely expended all his mana.

* Quill Spray is very effective against Io, as it has very low armor and has to stay close to the fight to not break its Tether.

* Skywrath mage also has a terrible time fighting against anything that isn't a hero. As Mystic Flare only affects heroes, 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 silence such as Riki, Silencer, or Night Stalker prevents Skywrath Mage from using his spells.

* Skywrath mage also has a terrible time fighting against anything that isn't a hero. As Mystic Flare only affects heroes, 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.

* Lone Druid's early game is good against slow, squishy supports since his bear is very strong early game and an Entangling Claws proc almost always guarantees a kill: Ancient Apparition, Crystal Maiden, Shadow Shaman, Skywrath Mage etc.

* Heroes with little health or magic resistance are easily picked off with Oracle's magic burst, such as Skywrath Mage, Crystal Maiden, or Enchantress.

* Heroes that are hard to gank: Axe, Death Prophet, Phantom Lancer

* Squishy heroes (Io, Crystal Maiden, Lina...), as Earth Spirit can deal tons of damage with Magnetize.

* Heroes with silence such as Riki, Silencer, or Night Stalker prevents Skywrath Mage from using his spells.

* Heroes that can easily bypass Io's allies to get to Io: Riki, Tusk, Clinkz, Sniper

* Heroes that are hard to gank: Axe, Death Prophet, Phantom Lancer

* Skywrath's pitiful defences also make him easy meat to heroes with high physical burst like Juggernaut or Phantom Assassin, the latter occasionally downing a support Skywrath in a single Stifling Dagger.

* Phantom Strike allows Phantom Assassin jump directly to Io.
* Coup de Grace makes short work of Io's low health and armor.

* Heroes with a low health pool (Crystal Maiden, Skywrath Mage etc)

* Squishy heroes, usually supports, like Io, Ancient Apparition, Keeper of the Light etc can die instantly from Tiny's magic burst.

* Strafe and Searing Arrows allow Clinkz to quickly kill Io due to its low armor.

* Ice Blast prevents Io from healing the target.
Additional:
* Ice Blast prevents Io from healing an ally with Tether and prevents healing from Overcharge
* Io is a common Mekansm builder which is useless if he is affected by Ice Blast.

* Berserker's Blood works proportionate to lost health, but Huskar has a decent health pool, and the attack speed granted from Berserker's Blood powers him up.
* Skywrath's armor and agility gain is very low so Huskar can outdamage him or take Skywrath down with him.

* Counterspell gives Anti-Mage magic resistance to negate a majority of Skywraith Mage's magical damage.
* Anti-Mage often builds Black King Bar and Manta Style which can dispel Ancient Seal and Concussive Shot.
* Huge mana cost on Mystic Flare means easy target for Mana Void.
* However, Anti-Mage is weak early-game to Ancient Seal until he can dispel silences, but still, Skywrath's solo kill potential is very low.

* Grimstroke can catch Io and his ally easily with SoulBind as Io has a tendency to tether himself with an ally frequently.
* Io is highly vulnerable to disables. Hence, Grimstroke's Phantom's Embrace is a great ability to hinder Io's potential.
Additional:
* Soulbind can target both Io and its Tethered ally, allowing Grimstroke and his team to target both with single target spells. Should Io try to Relocate, Phantom's Embrace can stop its channel to prevent escape.

* Take Aim and Assassinate allow Sniper to reach Io even if it stays in the backline.