Skywrath Mage
* 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.
Additional:
* 
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 Pugna at all.
Mars
* 
Nether Blast, Decrepify and 
Life Drain deal high magical damage and bypasses Bulwark.
* Nether Ward reduces the amount of abilities Mars can use during fights and forces Mars to be careful about the heavy mana cost of Arena Of Blood.
* Pugna is one of few heroes that can contest Mars' ability to push and defend towers early on.
Skywrath Mage
* Fate Edict can completely negate Skywrath Mage's heavy magic damage.
* Fortune End dispels 
Ancient Seal.
Mars
* Heroes with high magical or pure damage will bypass Bulwark: 
Timbersaw, 
Dark Willow, 
Enigma, 
Invoker, 
Pugna, 
Skywrath Mage, 
Tinker, 
Zeus, 
Oracle.
Skywrath Mage
* Heroes with a low health pool (
Crystal Maiden, Skywrath Mage etc)
Mars
* 
Shadowraze deals magic damage and ignores Bulwark.
* 
Requiem of Souls deals magic damage and can fear Mars away, forcing him to turn around and therefore become vulnerable.
Skywrath Mage
* Skywrath Mage's armor and agility gain is very low, so when Huskar's 
Burning Spears stack they can take him down very quickly at any point of the game.
* 
Berserker's Blood grants bonuses as Huskar uses Burning Spears to harass Skywrath Mage, granting him attack speed, magic resistance, and strength as health regen, making it possible that Huskar can harass Skywrath Mage out of lane and sustain through his magic burst through staying injured throughout lane, or even the game.
* 
Life Break allows Huskar to jump onto Skywrath Mage, closing the distance between them and busting him down so he cannot run. This can be combed with 
Inner Fire, adding a movement speed slow if Aghanim's Shard is applied so Skywrath Mage cannot escape.
Mars
* Burning Spear's magical damage is very troublesome for Mars in the laning stage.
* Life Break's percentage-based magical damage bypasses Bulwark, and can also be used to jump in or out of Arena Of Blood.
Skywrath Mage
* Heroes with high magical burst can easily kill Huskar when he is at low health: 
Lion, 
Lina, Skywrath Mage
Skywrath Mage
* 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.
* However, Skywrath Mage can easily kill Riki if he manages to root Riki with Rod of Atos or Gleipnir, followed by Dust of Appearance, Ancient Seal and Mystic Flare.
Mars
* 
Blink Strike gives bonus backstab damage and can bypass Bulwark. Defensively, it could be used to teleport away from Mars, especially while inside Arena of Blood.
* 
Smoke Screen can interrupt Mars' skill combos, especially when cast inside Arena of Blood.
* 
Tricks of the Trade can be used to evade Mars' skills, which have a slight delay to them. It could also be used to buy himself time while trapped inside of Arena of Blood.
Additional:
* 
Bulwark is generally irrelevant against Riki as he primarily deals bonus damage from behind.
Mars
* Heroes who rely on their target to run away: 
Riki, 
Bounty Hunter.
Mars
* 
Rage, acting as a pseudo-Black King Bar, completely negates Mars' initiation if used in time.
* 
Feast does damage and heals based on max health, perfect against high-health strength heroes like Mars.
* 
Infest allows Lifestealer to potentially save allies from Mars' initiation with a quick burst of extra health.
Mars
* 
Dragon Slave deals reliable magic damage during the laning phase against Mars.
* Lina's 
Eul's Scepter of Divinity and 
Light Strike Array combo can interrupt Mars from being disruptive for a decent amount of time and leave him vulnerable for follow up stuns.
* 
Laguna Blade deals massive magical damage, and pure damage with 
Aghanim's Scepter.
Mars
* Solar Guardian can save allies caught inside 
Arena of Blood.
Mars
* 
Berserker's Call forces Mars to face in the direction choosen.
* 
Counter Helix deals pure damage and can go through Bulwark.
Mars
* 
Decay, 
Soul Rip and 
Flesh Golem all deal magical damage which ignores Bulwark.
* Decay reduces Mars' natural strength and therefore his health pool, which is what he relies on to trade effectively in lane.
Mars
* It is difficult for Mars to trade blows with Ogre Magi in the early game thanks to his high base health, resistance and 
Ignite.
* 
Bloodlust can assist Ogre Magi or an ally in repositioning against Mars for its move speed bonus.
* 
Fireblast can interrupt and mitigate Mars from performing his skill combos, especially in combination with 
Multicast.
Mars
* Rebound allows her to jump in or out of the Arena Of Blood. She can save her allies from the Arena with Dispose as well.
Mars
* 
Nethertoxin breaks the damage block from Bulwark.
* 
Poison Attack and 
Viper Strike's slows make it difficult for Mars to contribute to fights due to his low mobility.
Additional:
* Viper Strike can disable Bulwark entirely, making Mars far less tanky. Using Nethertoxin inside Arena of Blood may discourage enemies from following up with Mars's initiation.
* 
Rod of Atos is currently common on Viper and keeps Mars in position long enough to be killed.
* However, Viper is not very tanky earlier in the game, so positioning against Mars is important for Viper since a well-timed 
Spear of Mars can be the end of Viper.
Mars
* Necrophos' largely magical damage completely ignores Bulwark.
* 
Ghost Shroud protects Necrophos from God's Rebuke but more importantly stops Mars from being a threat in lane.
Skywrath Mage
* 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.
Mars
* Venomancer's spells all deal magical damage, ignoring Bulwark.
* Venomancer's multiple slows are especially effective at kiting Mars.
* 
Plague Ward can attack through Arena Of Blood.
Additional:
* Venomancer's poison attacks are all magical damage, ignoring Bulwark.
* Venomancer's multiple slows are especially effective against Mars' low mobility.
* Plague Wards can attack through Arena of Blood.
Mars
* 
Swashbuckle is an auto attack and therefore ignores Mars' Bulwark.
* 
Shield Crash upgraded with Aghanim is an auto attack and therefore ignores Mars' Bulwark.
* 
Rolling Thunder makes him immune to magic, making Pangolier able to roll in and out of Mars' Arena Of Blood.
Mars
* 
Snowball can protect Tusk and his teammates from a Spear of Mars' stun after an Arena of Blood, and with proper targeting, even bring them out of the Arena. This is especially noticeable in the earlier stages of the game before allies buy Black King Bar and rely on this less. Even during the late-game, Tusk can purchase a 
Blink Dagger to save allies that are caught before Black King Bars can be used by Blinking in and Snowballing out.
* 
Tag Team is a constant threat to Mars in-lane, as it deals significant damage and slow, making Bulwark slightly ineffective.
* It is worth noting that 
Ice Shards can be detrimental to Tusk's own team by creating terrain that Spear of Mars can latch on, though using it conservatively is a good enough solution in most cases.
Skywrath Mage
* Templar Assassin easily withstands all the damage from Skyrwrath Mage, thanks to its first ability 
Refraction. In addition, Templar Assassin can kill Skywrath Mage with a single hit from under the second ability 
Meld.
Additional:
* Templar Assassin easily withstands all the damage from Skyrwrath Mage, thanks to its first ability Refraction. In addition, Templar Assassin can kill Skywrath Mage with a single hit from under the second ability Meld.
Mars
* 
Sticky Napalm slows turn rate, making it difficult for Mars to face frontwards, where Spear of Mars and Bulwark are effective. In combination with 
Firefly, which deals magic damage, Batrider can make quick work of Mars.
* 
Flaming Lasso disables Mars while enemies re-position themselves behind Mars to avoid Bulwark.
Skywrath Mage
* Heroes with silence such as Riki, 
Silencer, or 
Night Stalker prevents Skywrath Mage from using his spells.
Mars
* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.
Mars
* Heroes that depend on disrupting fights with ability combos or big ultimate abilities are vulnerable to the long stun of Fiend's Grip: 
Disruptor, 
Death Prophet, Enigma, 
Faceless Void, Invoker, 
Lich, 
Magnus, 
Mars, 
Medusa, 
Outworld Destroyer, 
Phoenix, 
Puck, 
Queen of Pain, 
Shadow Fiend, 
Treant Protector, 
Underlord, 
Winter Wyvern, 
Witch Doctor, Zeus.
Mars
* Heroes that can save their allies can be a big problem for Mars: 
Dazzle, 
Omniknight.
Mars
* 
Ursa is a special mention because despite Bulwark diminishing most of the damage Ursa does, he is quite durable, especially with 
Enrage, discouraging the aggressive all-in playstyle of Mars; Ursa can simply not target Mars.
Skywrath Mage
* Slow-moving projectiles: Skywrath Mage, Tinker, 
Necrophos
Additional:
* 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.
* 
Mind Flare turns Skywrath Mage's high intelligence growth against him and deals heavy damage.
* 
Spiked Carapace gives Nyx some degree of protection against Skywrath's spells.
Skywrath Mage
* Once you get a Black King Bar, squishy spellcasters like Zeus, Skywrath Mage and others will be probably easy to deal with.
Mars
* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.
Mars
* Heroes with break abilities: 
Shadow Demon (with Aghanim's Scepter), 
Viper.
Skywrath Mage
* 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.
Skywrath Mage
* Skywrath's pitiful defences also make him easy meat to heroes with high burst like 
Juggernaut, Lion, or 
Phantom Assassin, the latter occasionally downing a support Skywrath in a single 
Stifling Dagger.
Skywrath Mage
* 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.
Mars
* 
Kunkka's 
Ghostship and 
Torrent disrupt fights in Arena Of Blood.
Mars
* Heroes that can save their allies can be a big problem for Mars: Dazzle, Omniknight.
Mars
* Mars' own father is a formidable foe because Zeus deals massive amounts of magical damage. The high damage, low cooldown nukes of 
Arc Lightning and 
Lightning Bolt combined with the percent health magic damage of 
Static Field will shred Mars' health because it bypasses Bulwark completely.
Skywrath Mage
* Heroes with long range abilities are also able to touch Zeus, such as 
Clockwerk, Kunkka, Puck, Skywrath Mage, 
Spirit Breaker, 
Tusk and others.
Mars
* 
Firestorm and 
Pit of Malice are very disruptive in team fights, completely matching Mars especially since it can all be cast inside Arena Of Blood and also does percentage-based magical damage, negating Bulwark.
* 
Dark Rift can save any allies of Underlord trapped in Arena Of Blood.
* 
Atrophy Aura allows Underlord to lane against Mars quite well since he does not have the best base damage during the early game.
* Underlord is a common carrier of both 
Pipe of Insight and 
Mekansm/
Guardian Greaves, allowing his team to combat Mars in the mid to late game.
Mars
* Heroes with strong area-of-effect damaging and/or disabling abilities will be able to intercept Underlord and his team when they exit from Fiend's Gate: 
Luna's Aghanim's Scepter upgraded 
Eclipse, 
Dawnbreaker's 
Solar Guardian, 
Axe's Berserker's Call, Mars's Arena of Blood, 
Jakiro's 
Macropyre, 
Dual Breath and 
Ice Path, 
Naga Siren's 
Song of the Siren, 
Razor's 
Eye of the Storm and 
Plasma Field, Lina's Light Strike Array, 
Broodmother's 
Spinner's Snare from Aghanim's Scepter, 
Elder Titan's 
Earth Splitter and 
Echo Stomp, 
Alchemist's 
Unstable Concoction and 
Acid Spray, Queen of Pain's 
Sonic Wave, 
Dark Seer's 
Wall of Replica and 
Vacuum, 
Venomancer's 
Noxious Plague and 
Poison Nova from Aghanim's Scepter, Oracle's 
Fortune's End and 
Rain of Destiny from 
Aghanim's Shard, 
Bloodseeker's 
Blood Rite, Enigma's 
Black Hole and 
Midnight Pulse, Shadow Fiend's Requiem of Souls, 
Batrider's Aghanim's Scepter upgraded Flaming Lasso, Firefly, 
Flamebreak and Sticky Napalm, 
Ancient Apparition's 
Ice Blast, 
Sand King's 
Epicenter, 
Sand Storm and 
Burrowstrike, 
Gyrocopter's 
Call Down, 
Ember Spirit's 
Sleight of Fist, Death Prophet's 
Exorcism and 
Silence, 
Monkey King's 
Wukong's Command, Crystal Maiden's 
Freezing Field, 
Muerta's 
The Calling, Medusa's 
Stone Gaze, Zeus's 
Nimbus from Aghanim's Scepter. Dark Willow's 
Bramble Maze, 
Pangolier's Swashbuckle, 
Grimstroke's 
Soulbind, 
Ink Swell and 
Stroke of Fate, 
Earthshaker's 
Echo Slam and 
Fissure, Puck's 
Dream Coil and 
Waning Rift, Winter Wyvern's 
Winter's Curse, Magnus's 
Reverse Polarity.
Mars
* Time Dilation while Spear of Mars and 
God's Rebuke are on cooldown will make these abilities unusable for a long time, rendering Mars nearly useless.
* Mars cannot turn inside the Chronosphere, which makes it easy to attack him from the back, bypassing Bulwark completely.
Additional:
* 
Time Walk allows Faceless Void to escape or enter Arena Of Blood, and helps him recover from Mars' burst damage.
* 
Time Lock's magical damage ignores Bulwark.
* 
Chronosphere allows Faceless Void to reposition behind Mars, ignoring his Bulwark while he is helplessly frozen in time.
Skywrath Mage
* Heroes that can easily kill Faceless Void from outside his Cronosphere; 
Sniper, Skywrath Mage, etc.
Skywrath Mage
* 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.
Mars
* Nukers who have set amounts of damage will really struggle against Lone Druid especially in True Form: Puck, 
Void Spirit, Mars.
Skywrath Mage
* 
Mystic Flare can be used to effectively ignore the Spirit Bear entirely and burst Lone Druid during the early mid game.
* 
Concussive Shot and 
Arcane Bolt will provide vision of Lone Druid allowing for better chase in teamfights before the Spirit Bear can do too much damage.
* Ancient Seal denies the ability to transform into 
True Form and receive bonus HP from the skill.
Skywrath Mage
* Arcane Bolt can target Terrorblade's low health pool in the laning phase.
* Ancient Seal can prevent Terrorblade from casting Sunder.
* Mystic Flare can be used to great effect to burst Terrorblade down before he gets a 
Manta Style or a Black King Bar.
Mars
* Bulwark negates most of the physical damage from Terrorblade and his illusions.
* God's Rebuke and Spear of Mars can decimate Terrorblade's illusions quickly.
Skywrath Mage
* Even though 
Linken's Sphere will block your silence, you can cast Arcane Bolt to break it or wait until someone on your team breaks it. In addition, Linken's Sphere builders are usually squishy targets vulnerable to silences: 
Weaver, Queen of Pain, 
Morphling, 
Clinkz, etc. Don't forget that Ancient Seal also increases the magical damage these enemies take, along with silencing them.
Additional:
* Arcane Bolt has a long range and a low cooldown, and is a great spell to waste Linken's Sphere. It also serves as an effective spell to harass Weaver with.
* Ancient Seal prevents Weaver from using Shukuchi or Time Lapse.
Mars
* 
Shukuchi cannot help Weaver escape from Arena of Blood, and can most likely die if detected through invisibility.
* If pinned to the arena's walls, 
Time Lapse tends to not be enough to save Weaver, as God's Rebuke can keep him burst down thanks to its damage scaling.
* 
The Swarm and 
Geminate Attack are not enough to pierce through Bulwark.
Skywrath Mage
* Skywrath's pitiful defences also make him easy meat to heroes with high burst like Juggernaut, Lion, or Phantom Assassin, the latter occasionally downing a support Skywrath in a single Stifling Dagger.
Skywrath Mage
* While Phantom Assassin can kill Skywrath Mage in a few strikes, Skywrath Mage can also do the same to her if she is not careful.
* Arcane Bolt's long range and low cooldowns allows Skywrath Mage to severely harass Phantom Assassin in lane.
* Ancient Seal prevents Phantom Assassin from escaping or engaging with 
Phantom Strike.
* Mystic Flare's heavy magical damage nukes Phantom Assassin down quickly during the early to mid game.
Additional:
* While Phantom Assassin can kill Skywrath Mage in a few strikes, Skywrath Mage can also do the same to her if she is not careful.
* Arcane Bolt's long range and low cooldowns allows Skywrath Mage to severely harass Phantom Assassin in lane.
* Ancient Seal prevents Phantom Assassin from escaping or engaging with Phantom Strike.
* Mystic Flare's heavy magical damage nukes Phantom Assassin down quickly during the early to mid game.
Mars
* Phantom Assassin's high physical damage is greatly reduced by Bulwark.
* God's Rebuke has true strike, ignoring the evasion from 
Blur.
Mars
* 
Legion Commander is both good and bad vs Mars, on the plus side she can dispel Spear of Mars with 
Press the Attack and is a good 
Silver Edge carrier. However, Mars is not an ideal 
Duel target, as Bulwark will force her to 1: Buy Silver Edge, and 2: Hit Mars with it before the Duel, allowing a skilled Mars to react, especially with Eul's Scepter of Divinity. In teamfights, Mars will happily draw attention after using his abilities, and tank the Duel with all spells on cooldown.
Skywrath Mage
* Mystic Flare can easily burst down Legion Commander while she is Dueling.
Mars
* Because Duel requires both combatants to face each other, Bulwark's effectiveness will be increased by a huge margin, which makes it much more difficult for Legion Commander to win any duels against him.
* Spear of Mars and God's Rebuke pushes Legion Commander away during Duels against allies.
Additional:
* Bulwark immensely mitigates Duel, even with bonus physical damage, as Bulwark scales by percentage. Mars can also buy time for a dueled ally by pushing Legion Commander away with Spear of Mars.
Skywrath Mage
* Even though Linken's Sphere will block your silence, you can cast Arcane Bolt to break it or wait until someone on your team breaks it. In addition, Linken's Sphere builders are usually squishy targets vulnerable to silences: Weaver, Queen of Pain, Morphling, Clinkz, etc. Don't forget that Ancient Seal also increases the magical damage these enemies take, along with silencing them.
Mars
* Heroes who cannot fight back during Arena of Blood in the early and mid game: 
Abaddon, 
Anti-Mage, Broodmother, Luna, Sniper, 
Troll Warlord, Weaver, Clinkz.
Skywrath Mage
* Heroes with either magical, physical or pure damage burst: 
Bane, Ember Spirit, 
Leshrac, Lina, Luna, 
Nyx Assassin, Phantom Assassin, Skywrath Mage, Tinker, Ursa, Void Spirit.
Mars
* Heroes that are hard to gank: Axe, Death Prophet, Phantom Lancer, 
Slark, 
Centaur Warrunner, 
Bristleback, Medusa, Mars.
Skywrath Mage
* Lich is heavily reliant on his abilities to contribute to team fights, so be wary of enemies that can Silence: Bloodseeker, Death Prophet, Silencer, 
Drow Ranger, Skywrath Mage.
Mars
* Heroes who lack burst damage will have a hard time against Mars: Phantom Lancer, 
Nature's Prophet, Lich.
Mars
* Even if he can slow Mars down with 
Shrapnel and 
Headshot, Mars can tank Sniper's physical damage simply by facing him with Bulwark, allowing him to endure his auto-attacks into the late-game. Should Sniper choose to attack someone else, Mars can redirect his projectiles with Bulwark's active ability.
* Sniper's poor mobility makes him very vulnerable to Arena of Blood, especially in the early game. Mars can also take advantage of this by pushing him closer to the front line with Spear of Mars.
Mars
* Bulwark blocks much of Slark's basic attack damage, even during 
Shadow Dance.
* Slark finds it very difficult to have a good early/mid game when pressured in the early game by Spear of Mars and God's Rebuke.
* Spear of Mars and God's Rebuke can hit Slark through Shadow Dance and 
Depth Shroud.
* Should 
Pounce be on cooldown, Slark is very vulnerable inside Arena of Blood.
Skywrath Mage
* Ancient Seal can silence Jakiro and make him vulnerable to magical spells up to 6 seconds.
* Skywrath Mage can usually burst down Jakiro with his high damage magical spells.
Skywrath Mage
* A good Skywrath Mage with quick fingers will punish Queen of Pain for blinking aggressively. Ancient Seal is a six second silence with no cast time, so he can interrupt either her Shadow Strike or Sonic Wave, and a good Mystic Flare on top of that will seal the deal for her.
* Ancient Seal also has pretty good range so he could get it off before she blinks away.
Skywrath Mage
* Arcane Bolt's low cooldown allows him to deal consistent damage to Morphling, and is a viable way to disable Linken's Sphere.
* Ancient Seal prevents Morphling from using any of his skills, giving Skywrath Mage and his team ample time to burst Morphling down.
* Mystic Flare coupled with a stun/root can easily burst Morphling down, especially if he has more stats shifted to Agility.
* Alternatively, Morphling can use Morph to use Skywrath Mage's own silence and nukes against him.
Skywrath Mage
* Skywrath Mage can easily harass Alchemist in the laning phase with multiple Arcane Bolts. Additionally, if Alchemist is in the process of throwing an Unstable Concoction, and has no way to dispel Ancient Seal, the self stun becomes an easy set up for Mystic Flare.
* Caution, however, as a decently farmed Alchemist with {Item ID:Radiance} and {Item ID:Manta Style} can easily send illusions to harass and force Skywrath Mage out.
Skywrath Mage
* Arcane Bolt allows Skywrath Mage to harass Earthshaker out of lane.
* Ancient Seal is an instant silence that can be pre-cast onto Earthshaker to disrupt his combo, before he uses Blink Dagger to initiate.
* Mystic Flare will nuke Earthshaker down while he stands in place during his long cast animations.
Mars
* As long as Mars is facing her with Bulwark, even if pushed away with 
Gust, Drow Ranger will do no effectual damage against him. Mars' ability to endure her onslaught usually gives him enough time to cast Arena of Blood, of which she has a very slim chance surviving without Gust.
* With Bulwark's active ability, Mars can protect allies pursued by Drow Ranger by redirecting her projectiles to his shield instead.
Skywrath Mage
* Skywrath Mage should have the upper hand against Vengeful Spirit with Ancient Seal.
* Vengeful is highly dependant on her abilities and has no natural means to deal against silences.
* Her low attack range allows Skywrath Mage to easily bully her out of the lane.
Mars
* Spectre cannot have a good game if she is pressured heavily in lane, which is something Mars can do. He may even force her to cast 
Haunt as an escape, putting it on a long cooldown.
* Should Spectre get to the late game, Mars can block a large amount of her damage with Bulwark and can mitigate some of the chaos caused by her Haunt illusions with God's Rebuke.
Skywrath Mage
* 
Cold Embrace is a perfect setup for Mystic Flare.
* Winter Wyvern is a spellcaster, and the 6 second silence from Ancient Seal can prevent her from contributing much.
* Because Skywrath Mage tends to stay back in fights, Winter Wyvern will have to get close to a teamfight to cast Winter's Curse on him. And if she chooses to cast it on one of his allies, his low attack speed and damage means that he won't do much.
* However, bear in mind that Skywrath Mage has seriously awful armor, and that can make him an adequate target to being turned against his own team with Winter's Curse, which can result in his death quickly.
Additional:
* Cold Embrace is the perfect setup for Mystic Flare, and his 6-second silence is good against Winter Wyvern in general.
Skywrath Mage
* Ancient Seal's instant cast time will often silence Brewmaster before he can do anything.
* Brewmaster also has no defense against Skywrath Mage's massive magical damage.
Mars
* Arena Of Blood prevents Bloodseeker from attacking a 
Ruptured target.
* Bulwark helps Mars survive Rupture ganks simply by turning towards Bloodseeker without moving.
* Spear of Mars and God's Rebuke can push Bloodseeker from Ruptured targets.
Skywrath Mage
* 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.
Mars
* Heroes who cannot fight back during Arena of Blood in the early and mid game: Abaddon, Anti-Mage, Broodmother, Luna, Sniper, Troll Warlord, Weaver, Clinkz.
Mars
* 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.
Skywrath Mage
* Heroes with nukes: Bane, Lich, Lion, Skywrath Mage
Additional:
* 
Untouchable is useless versus constant Arcane Bolts, and it doesn't help that her strength gain is the lowest in the game.
* A jungle Enchantress can weaken lanes and make Skywrath Mage's job easier.
* The magic amplification from Ancient Seal makes her even squishier to Skywrath and his allies' magic nukes.
Mars
* Heroes that can negate Hoodwink's mobility: Kunkka, Disruptor, Mars.
Mars
* Heroes who lack burst damage will have a hard time against Mars: Phantom Lancer, Nature's Prophet, Lich.
Mars
* Heroes who can disable Mars but cannot do any damage to him, meaning he just tanks their abilities: 
Doom, Magnus.
Mars
* Heroes with the capability of removing or destroying trees greatly hinders the effectiveness of Treant Protector's abilities: Batrider, Nature's Prophet, Lina, Enigma, Mars
Skywrath Mage
* Heroes with either magical, physical or pure damage burst: Bane, Ember Spirit, Leshrac, Lina, Luna, Nyx Assassin, Phantom Assassin, Skywrath Mage, Tinker, Ursa, Void Spirit.
Mars
* Heroes who cannot fight back during Arena of Blood in the early and mid game: Abaddon, Anti-Mage, Broodmother, Luna, Sniper, Troll Warlord, Weaver, Clinkz.
Skywrath Mage
* Heroes with powerful spammable abilities will prove problematic for Grimstroke as Ink Swell does not protect him from them: Zeus, Skywrath Mage, Tinker, Lina
Mars
* 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.
Mars
* Durable heroes: Axe, Dawnbreaker, Bristleback, Mars, Omniknight, Tidehunter, Wraith King, 
Primal Beast, Underlord.
Skywrath Mage
* 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.
Mars
* Heroes who cannot fight back during Arena of Blood in the early and mid game: Abaddon, Anti-Mage, Broodmother, Luna, Sniper, Troll Warlord, Weaver, Clinkz.
Skywrath Mage
* Skywrath Mage's Mystic Flare can deal huge damage to Clockwerk inside his Power Cogs.
Mars
* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.
Skywrath Mage
* Magical burst damage is Timbersaw's weakness, and Ancient Seal not only amplifies it but also prevents him from using 
Timber Chain to escape for up to 6 seconds.
* He generally doesn't build early items to deal with silences.
* 
Reactive Armor does not trigger on magic damage or spells, meaning that even a Pipe of Insight won't give him the massive sustain he normally gets from attacks.
Additional:
* Skywrath Mage's long range and low cooldown magic damage spells can easily harass Timbersaw out of lane.
* Ancient Seal is not only a long lasting silence, (one of Timbersaw's biggest weaknesses) but it also makes him even more vulnerable to magical burst damage.
Mars
* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.
Skywrath Mage
* Skywrath Mage stands perfectly on the center line against Tinker, thanks to his nuke and silence. Also, thanks to his abilities, he can quickly kill a victim, and Tinker is one of the most subtle heroes in the game
Additional:
* Skywrath Mage stands perfectly on the center line against Tinker, thanks to his nuke and silence. Also, thanks to his abilities, he can quickly kill a victim, and Tinker is one of the most subtle heroes in the game
Mars
* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.
Skywrath Mage
* Ancient Seal instantly shuts down Dark Willow's abilities, rendering her defenseless against his high burst damage spells, while she cannot cast spells of her own.
* Mystic Flare deals immense burst damage in an area, damaging Dark Willow through Shadow Realm.
Skywrath Mage
* Skywrath's pitiful defences also make him easy meat to heroes with high burst like Juggernaut, Lion, or Phantom Assassin, the latter occasionally downing a support Skywrath in a single Stifling Dagger.
Mars
* Bulwark mitigates 
Omnislash which deals physical damage, severely reducing its damage.
* Omnislash switch to opposite direction with each slash, so Mars can easily reduce most of its damage.
* However because {Ability ID:Blade Fury|Juggernaut} gives spell immunity Juggernaut can easily escape from {Ability ID:Arena Of Blood|Mars}.
Additional:
* Juggernaut deals mostly physical damage, which is easily mitigated with Bulwark.
* Juggernaut's Omnislash switches to opposite directions which each slash, so Mars can mitigate most of its damage since he only takes full damage from one direction: his back.
Mars
* Medusa's Stone Gaze forces Mars to choose between getting petrified, or turning his vulnerable back on Medusa.
Mars
* Bulwark can make each of Medusa's attacks target him instead, reducing Medusa's contribution on team fights.
* Spear of Mars stuns Medusa and also pushes her away from teamfights, taking advantage of Medusa's low mobility.
* Arena Of Blood blocks Medusa's attacks from outside the arena.
Skywrath Mage
* Skywrath Mage's abilities are single targeted and he can't use Mystic Flare to its fullest potential, since all Meepos spread the damage between them. He also has no disables to prevent Meepo from Poofing to another one (unless he can get Ancient Seal off first).
Mars
* Bulwark blocks the attack from Meepo and his clones.
* Spear of Mars & God's Rebuke prevents Meepo and his clones from initiation or escaping.
Skywrath Mage
* 
Mana Break drains Skywrath Mage of his mana, slowing him and dealing bonus damage while rendering him unable to cast his spells.
* 
Blink makes it incredibly easy for Anti-Mage to close the gap between himself Skywrath Mage to right-click him down. He can also use Blink to get away and escape into fog of war.
* Anti-Mage passively reduces enemy spell damage with 
Counterspell, and can activate the ability to block and send back Skywrath's Ancient Seal or Arcane Bolt, causing him to silence himself or deal massive damage to himself.
* Skywrath Mage's large mana-costs makes him an easy target for 
Mana Void.
* Anti-Mage often builds Black King Bar and Manta Style which can dispel Ancient Seal and Concussive Shot.
Skywrath Mage
* Heroes with abilities or items that can silence or disable Anti-Mage for long periods of time will prevent him from Blinking away: Lion, Silencer, Shadow Shaman, Grimstroke, Witch Doctor, Riki, Faceless Void, Skywrath Mage, Puck.
Mars
* Heroes who cannot fight back during Arena of Blood in the early and mid game: Abaddon, Anti-Mage, Broodmother, Luna, Sniper, Troll Warlord, Weaver, Clinkz.
Skywrath Mage
* Skywrath Mage's very low health allows Monkey King to ambush and finish him off quickly.
Mars
* If visible, Mars can knock Monkey King off his 
Tree Dance with God's Rebuke, as well as Spear of Mars. Arena of Blood also destroys a large swath of trees, which can disrupt Monkey King's positioning and turn him vulnerable should he choose to hide in trees.
* Mars can endure 
Jingu Mastery attacks simply by facing him with Bulwark.
* Mars can end Wukong's Command early by displacing Monkey King with a well-thrown Spear of Mars. Mars can also endure most of his clones with Bulwark.
Additional:
* Monkey King's natural reliance on trees makes him an exceptionally prime target for Spear of Mars. Should Monkey King use Mischief to disguise himself, it will still hit him, stunning him in the process.
* God's Rebuke easily pushes Monkey King out of Wukong's Command.
Skywrath Mage
* 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.
Mars
* Heroes who lack burst damage will have a hard time against Mars: Phantom Lancer, Nature's Prophet, Lich.
Mars
* 
Ball Lightning makes it almost impossible to catch Storm Spirit without someone else initiating for you.
* 
Overload is not reduced by Bulwark and the magical damage spam can wear down Mars quickly.
Additional:
* Storm Spirit's abilities all do magical damage, which can bypass Bulwark.
* Ball Lightning can escape through Arena of Blood and it is easy to dodge Spear of Mars.
Skywrath Mage
* Similar to Timbersaw, Storm Spirit builds items that don't help against silences.
* An 
Orchid Malevolence will most likely silence you first. However, if you grab a Eul's Scepter of Divinity, you might dispel his silence and turn the tides to your favor.
* Root and silence are 
Storm Spirit's ultimate counters. Skywrath Mage has a silence in his kit, and has Rod of Atos as his core item. If he dispels one, you cast the other, both leaving him vulnerable.
* If he builds Black King Bar, he spends 4050 gold that doesn't help him snowball effectively.
Mars
* Heroes with high health especially Strength heroes will take more damage on Sun Ray: Axe, 
Pudge, Bristleback, Mars.
Skywrath Mage
* Silence (and mana burns) will be a persistent problem for Phoenix, as it is heavily reliant on its abilities whether defensively or offensively, so heroes like Death Prophet, Skywrath Mage, and even Nyx Assassin must be closely observed to prevent being shut down by these heroes.
* Hexes are a greater threat to Phoenix as they also disable items, preventing Phoenix from dispelling the debuff on its own.
Skywrath Mage
* 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.
Mars
* Heroes who rely on their target to run away: Riki, Bounty Hunter.
Skywrath Mage
* Heroes with silence such as Riki, Silencer, or Night Stalker prevents Skywrath Mage from using his spells.
Mars
* Heroes that are hard to gank: 
Dragon Knight, Mars, Centaur Warrunner.
Skywrath Mage
* In general, heroes that deal burst in multiple instances will trigger Borrowed Time and heal Abaddon for a large amount, such as Skywrath Mage, 
Techies, Juggernaut, Shadow Shaman, or 
Ogre Magi.
Additional:
* 
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.
Mars
* Heroes who cannot fight back during Arena of Blood in the early and mid game: Abaddon, Anti-Mage, Broodmother, Luna, Sniper, Troll Warlord, Weaver, Clinkz.
Skywrath Mage
* Outworld Destroyer can steal more mana with
Astral Imprisonment from 
Skywrath Mage with 
Shield of the Scion (granted by 
Aghanim's Shard). Shield of the Scion grants Skywrath Mage bonus intelligence every time he deals magic damage to an enemy hero with his abilities. The higher his intelligence, the larger his mana pool. Since Astral Imprisonment steals based on the target's max mana, Outworld Destroyer can steal much more mana from Skywrath Mage.
Mars
*
Arcane Orb's pure damage ignores Mars' Bulwark.
Astral Imprisonment can be used to stop Mars from being disruptive or save allies from his abilities.
Sanity's Eclipse deals high damage to Mars, due to his low intelligence pool.
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