Dark Seer
* In general, heroes who are melee with no way to fight back can be very easily poked by Monkey King to gain his Jingu Mastery stacks: 
Dark Seer, 
Riki, 
Rubick.
Skywrath Mage
* Skywrath Mage's very low health allows Monkey King to ambush and finish him off quickly.
Dark Seer
* Dark Seer's strength lies in his high-mana cost skills. So 
Mana Break can be a great nuisance for him, since it can reduce his mana and prevent him from casting his spells.
* 
Mana Void can deal a lot of damage if Dark Seer spent a lot of mana on his abilities.
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.
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.
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.
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.
Dark Seer
* The constant dispel from Demonic Purge will make any attempt to save the victim or himself by 
Surge become futile. For what it's worth, Demonic Purge will also dispel 
Ion Shell.
Dark Seer
* 
X Marks the Spot prevents Dark Seer or his allies from escaping with Surge.
Dark Seer
* 
Flame Guard makes Dark Seer not deal any damage with his skills to Ember Spirit.
Dark Seer
* A Sniper who is somewhat competent at positioning is hardly going to be affected by any of Dark Seer's spells thanks to 
Take Aim.
* However, an illusion of Sniper made with Wall of Replica is extremely powerful, and hard to deal with.
Dark Seer
* 
Spell Steal will easily steal all abilities from Dark Seer.
Additional:
* Spell Steal can perfect from Rubick's steal all abilities from Dark Seer. Rubick's always purchase 
Aghanim's Scepter can two stolens abilities from Dark Seer's and waiting for seconds for second stolen abilities (example: combinated Vacuum and Wall of Replica) and many different combination.
* A good positoning from Rubick's Spell Steal waiting steal abilities from Dark Seer 
Wall of Replica and illusion from Wall of Replica Dark Seer's can fighting with effect from outcome steal Wall of Replica from Rubick's.
* Combinated Rubick's steal Surge and 
Blink Dagger is very important catch from Dark Seer's and enemies.
* Rubick's 
Telekinesis can lifted up Dark Seer or enemy heroes and throw to Wall of Replica from Rubick's steal.
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.
Dark Seer
* Heroes with fast movement abilities will suffer huge damage when afflicted by Rupture: 
Spirit Breaker, 
Earth Spirit, Dark Seer.
Additional:
* 
Rupture can deal a lot of damage to either a surged Dark Seer or his allies and prevent the target from getting into position.
Skywrath Mage
* Heroes with silence such as Riki, Silencer, or 
Night Stalker prevents Skywrath Mage from using his spells.
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.
Skywrath Mage
* Heroes with silence such as Riki, Silencer, or Night Stalker prevents Skywrath Mage from using his spells.
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.
Dark Seer
* Dark Seer relies on Surge for most of his mobility, so he's not very vulnerable to slows, but much more to root effects and walls or pseudo-walls such as 
Disruptor's 
Kinetic Field or 
Slark's 
Pounce.
Skywrath Mage
* Once you get a Black King Bar, squishy spellcasters like 
Zeus, Skywrath Mage and others will be probably easy to deal with.
Dark Seer
* Abilities that deal low damage with high amounts of instances are irrelevant against Pudge during Flesh Heap's active: 
Gyrocopter's 
Rocket Barrage and Dark Seer's Ion Shell are just a couple examples.
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
* Heroes with a low health pool (Crystal Maiden, Skywrath Mage etc)
Dark Seer
* Strong laners are usually at a disadvantage because of how well Sven can jungle. Heroes such as Dark Seer. 
Underlord and 
Legion Commander may find that later Sven takes care of them very quickly after some jungle farming.
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.
Skywrath Mage
* Heroes with high magical burst can easily kill Huskar when he is at low health: Lion, 
Lina, Skywrath Mage
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.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: 
Beastmaster, 
Broodmother, 
Enigma, 
Nature's Prophet, 
Visage, 
Warlock, 
Wraith King.
Dark Seer
* Dark Seer's 
Vacuum and Ion Shell allows him to clear a wave of Terrorblade's illusions.
* Because Terrorblade often builds items that require 
Ultimate Orb like Manta Style and 
Eye of Skadi, Dark Seer can create a very strong illusion of Terrorblade with Wall of Replica and 
Normal Punch from Aghanim's Scepter.
* If Dark Seer can use Vacuum to help teammates land their AoE abilities, Terrorblade will be quickly killed before he even gets a chance to use Sunder.
Additional:
* Dark Seer's Vacuum and Ion Shell allows him to clear a wave of Terrorblade's illusions.
* Because Terrorblade often builds items that require Ultimate Orb like Manta Style and Eye of Skadi, Dark Seer can create a very strong illusion of Terrorblade with Wall of Replica and Normal Punch from Aghanim's Scepter.
* If Dark Seer can use Vacuum to help teammates land their AoE abilities, Terrorblade will be quickly killed before he even gets a chance to use Sunder.
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.
Dark Seer
* Dark Seer's Vacuum and Ion Shell can clear a wave of Chen's Creeps effectively.
* Surge applies haste movement and negates the slow from 
Penitence, allowing Dark Seer to easily escape from Chen and his creeps.
* Dark Seer's full combo from Dark Seer's Vacuum, Wall of Replica and Normal Punch from Aghanim's Scepter can often kill Chen or any of his allies before he can save them with 
Hand of God.
Additional:
* Dark Seer's Vacuum and Ion Shell can clear a wave of Chen's Creeps effectively.
* Surge applies haste movement and negates the slow from Penitence, allowing Dark Seer to easily escape from Chen and his creeps.
* Dark Seer's full combo from Dark Seer's Vacuum, Wall of Replica and Normal Punch from Aghanim's Scepter can often kill Chen or any of his allies before he can save them with Hand of God.
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.
Dark Seer
* With Normal Punch from Aghanim's Scepter, Dark Seer can gain an advantage against heroes who rely on evasion as Normal Punch has true strike: Phantom Assassin, 
Windranger, 
Hoodwink.
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.
Dark Seer
* Heroes with haste can negate Enchant's slow: 
Weaver, Dark Seer, 
Lycan, 
Centaur Warrunner.
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.
Dark Seer
* The haste provided by Dark Seer's Surge or a {Rune:Haste} renders Lich's slows ineffective.
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.
Dark Seer
* 
Living Armor can be destroyed quickly with Ion Shell.
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.
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.
Dark Seer
* Venomancer is a low health hero and low range hero who is easy to harass with Ion Shell on a creep in the early game.
* Venomancer depends entirely on all his slows to keep distance or chase, but since Surge ignores slows, it is nearly impossible for Venomancer to hunt or run away from Dark Seer or his surged teammates.
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
* 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.
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
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
* 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.
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
* 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.
Dark Seer
* With Normal Punch from Aghanim's Scepter, Dark Seer can gain an advantage against heroes who rely on evasion as Normal Punch has true strike: Phantom Assassin, Windranger, Hoodwink.
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.
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.
Skywrath Mage
* Mystic Flare can easily burst down Legion Commander while she is Dueling.
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.
Dark Seer
* Ion Shell zones out Broodmother in the laning phase, and can kill her spiderlings if used on one Spiderling in a group.
* Vacuum can pull Broodmother out of the treeline.
Additional:
* Ion Shell is a very powerful weapon against Broodmother's Spiderlings and makes her laning much harder.
Dark Seer
* With Normal Punch from Aghanim's Scepter, Dark Seer can gain an advantage against heroes who rely on evasion as Normal Punch has true strike: Phantom Assassin, Windranger, Hoodwink.
Skywrath Mage
* Heroes that can easily kill Faceless Void from outside his Cronosphere; 
Sniper, Skywrath Mage, etc.
Dark Seer
* Heroes that rely on illusions typically spawn very strong illusions inside Dark Seer Wall of Replica that he can use against them or their team: 
Phantom Lancer, 
Chaos Knight, 
Naga Siren, 
Terrorblade.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Skywrath Mage
* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, 
Dark Willow, Enigma, 
Invoker, Pugna, Skywrath Mage, Tinker, Zeus, 
Oracle.
Dark Seer
* Certain heroes can mess up with Pangolier's positioning and timing (especially if he intends to use Rolling Thunder during combat): 
Vengeful Spirit, 
Keeper of the Light, 
Huskar, Dark Seer
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
Dark Seer
* Heroes with hastes: Dark Seer, Lycan
Dark Seer
* Dark Seer can increase the movement speed of allies with Surge, breaking Static Link.
Dark Seer
* Heroes who do not have nor rely on passive abilities make Nethertoxin much less effective: 
Clinkz, Pugna, Nature's Prophet, Dark Seer, Lycan, 
Tusk
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.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Additional:
* Surge allows for Dark Seer and his allies to escape from Upheaval due to it ignoring any slow.
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.
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
* Heroes with long range abilities are also able to touch Zeus, such as 
Clockwerk, 
Kunkka, Puck, Skywrath Mage, Spirit Breaker, Tusk and others.
Dark Seer
* Dark Seer can pull together Spectre's illusions with Vacuum, and Wall of Replica creates an illusion of Spectre that deals massive damage.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
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.
Skywrath Mage
* Skywrath Mage's Mystic Flare can deal huge damage to Clockwerk inside his Power Cogs.
Dark Seer
* Heroes with escape abilities: 
Anti-Mage Dark Seer Slark Storm Spirit Windranger Weaver can kite Lifestealer due to him having no lockdown.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Dark Seer
* Dark Seer's only disable is Vacuum. Though he starts off with high armor and health, he'll eventually have a hard time dealing with high mobility heroes such as Weaver or Queen of Pain.
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
* 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).
Dark Seer
* Dark Seer can take great advantage of 
Divided We Stand by putting an Ion Shell on a clone in order to harass them effectively.
* Vacuum can take a single Meepo and disable him for Dark Seer and his teammates to take out.
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
* 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
* 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.
Dark Seer
* Ion Shell destroys Refraction's protection stacks in short time.
* Surge ignores the massive slow from 
Psionic Trap.
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.
Dark Seer
* Heroes that rely on illusions typically spawn very strong illusions inside Dark Seer Wall of Replica that he can use against them or their team: Phantom Lancer, Chaos Knight, Naga Siren, Terrorblade.
Additional:
* Ion Shell helps taking down illusions quickly, making it easy to identify the real Phantom Lancer.
* Surge allows Dark Seer and his teammates to run away from Phantom Lancer, who relies on his 
Phantom Rush to chase enemies.
Dark Seer
* Dark Seer relies on Surge for most of his mobility, so he's not very vulnerable to slows, but much more to root effects and walls or pseudo-walls such as Disruptor's Kinetic Field or Slark's Pounce.
Dark Seer
* Heroes with AoE abilities will hit Slark in Shadow Dance: Lina, 
Jakiro, Underlord, Leshrac, Dark Seer, 
Earthshaker, Timbersaw, Crystal Maiden.
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.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Dark Seer
* Dark Seer's only disable is Vacuum. Though he starts off with high armor and health, he'll eventually have a hard time dealing with high mobility heroes such as Weaver or Queen of Pain.
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.
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.
Dark Seer
* Heroes that rely on illusions typically spawn very strong illusions inside Dark Seer Wall of Replica that he can use against them or their team: Phantom Lancer, Chaos Knight, Naga Siren, Terrorblade.
Dark Seer
* Heroes without blink mechanisms or spell immunity will have a hard time positioning against 
Pit of Malice: 
Sven, 
Tiny, Wraith King, 
Dragon Knight, 
Meepo, 
Doom, 
Bounty Hunter, Dark Seer, 
Undying, 
Alchemist, Legion Commander.
Dark Seer
* 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.
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.
Dark Seer
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: Jakiro, Viper, Venomancer, Huskar, Ember Spirit, Dark Seer, Sand King, Doom, Dawnbreaker. However, this also means they are easily stunned.
Dark Seer
*
Fortune's End dispels Ion Shell and Surge, making any gank attempt on Dark Seer in the laning phase likely to succeed.
Fate's Edict prevents all magical damage that comes from Dark Seer's abilities. 
Fortune's End dispels Ion Shell on creeps, which Dark Seer relies on to farm and zone.
Ion Shell, a skill that helps Dark Seer immensely in the laning phase, as well as 
Surge, a move-speed buff, effectively allowing Oracle to control Dark Seer, especially in the laning phase.
*
*
Additional:
* Fortune's End can dispel
Skywrath Mage
* Fate Edict can completely negate Skywrath Mage's heavy magic damage.
Ancient Seal.
* Fortune End dispels