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).
Phoenix
* Earthbind can prevent Phoenix from using 
Icarus Dive, the only escaping mechanism of this hero.
* Heavy burst damage from Poof can easily kill Phoenix even when it slows down all the Meepos with 
Fire Spirits.
* Meepo's clones destroy the Phoenix Sun from 
Supernova in no time, even when they are slowed down by Fire Spirits.
* Meepo's naturally high magic resistance gives Phoenix a hard time with bursting him down. He can even turn the tide if Icarus Dive is on cooldown.
Additional:
* Meepo is unlike any other multi-unit enemy Phoenix may face in the battlefield. Unlike illusion-based heroes like 
Phantom Lancer or 
Chaos Knight, Meepo's clones are not illusions, meaning they can deal full damage to the Phoenix Sun if all four (or five) are present.
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.
Phoenix
* Juggernaut's high attack speed lets him destroy a Supernova easily. He can even attack a Supernova during Blade Fury with his regular attacks.
* 
Blade Fury protects Juggernaut from all of Phoenix's spells (except Supernova, which pierces spell immunity).
* Blade Fury can also dispel the attack speed slow from Fire Spirits and the movement speed slow from Icarus Dive.
* Phoenix's Icarus Dive will not protect it from 
Omnislash unless it dives into creeps, and Phoenix's low armor makes for an easy kill.
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.
Phoenix
* Spiked Carapace reacts on any of the damage over time from Phoenix's abilities and can interrupt 
Sun Ray and Icarus Dive.
Skywrath Mage
* Heroes with silence such as 
Riki, 
Silencer, or 
Night Stalker prevents Skywrath Mage from using his spells.
Phoenix
* Silencer will most likely disrupt an initiation with his ultimate, 
Global Silence, prevent escape with his 
Last Word, and if Phoenix happens to die to him (or near him) enough times, he would sap enough of Phoenix's much needed Intelligence to make him a stronger foe and Phoenix with less mana than it already had.
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.
Phoenix
* Inner Beast helps Beastmaster's team destroy Supernova quickly.
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.
Phoenix
* Anti-Mage dispels Phoenix's slows with Manta Style.
* Anti-Mage can Blink directly next to Supernova, giving him more time to destroy the egg.
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
* 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.
Phoenix
* Huskar's high attack speed can counteract Fire Spirits, and easily destroy the Supernova.
Additional:
* Berserker's Blood will let Huskar easily face down a Supernova with increased attack speed.
* Icarus Dive may not be an easy escape from Huskar either as he can chase Phoenix during it with Life Break if Huskar times it right.
* However, Phoenix can buy items which can
Skywrath Mage
* Heroes with high magical burst can easily kill Huskar when he is at low health: Lion, 
Lina, Skywrath Mage
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.
Phoenix
* Heroes that deal damage over time will also fail to bring down Abaddon and his allies, such as 
Huskar, 
Venomancer, or 
Phoenix.
Phoenix
* Tempest Double, Magnetic Field's attack speed bonus, and Arc Warden's high attack range will easily destroy a Phoenix using Supernova much faster than usual.
* Phoenix is very weak against pushers, especially those like Arc Warden who can kill him easily, as his skillset works best in teamfights.
Additional:
* His 
Tempest Double is not an illusion, but rather a full hero unit, which effectively reduces half of the Supernova's health. His 
Magnetic Field can tremendously boost his attack speed, allowing him to destroy Supernova in no time even when he's affected by Fire Spirits.
Phoenix
* Ursa can easily unleash a number of attacks in an incredibly short amount of time, easily destroying the Supernova in a couple of seconds regardless of Fire Spirits' debuff. His 
Enrage also dampens any damage Phoenix might toss at his direction, as well as remove any debuffs Phoenix may place on him.
Skywrath Mage
* Heroes with silence such as Riki, Silencer, or Night Stalker prevents Skywrath Mage from using his spells.
Phoenix
* 
Void can interrupt Icarus Dive.
* His 
Crippling Fear's silence will shutdown a spell caster Phoenix.
* However, Phoenix punishes Night Stalker with Supernova because it will turn night into day, and it has a higher priority than 
Dark Ascension, effectively canceling the passive bonuses Night Stalker gets from 
Hunter in the Night.
Phoenix
* Phoenix turns night to day, overriding Dark Ascension during Supernova.
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.
Phoenix
* Phoenix expends health to use its abilities, making it a good target for Thirst.
* Rupture deals heavy damage against Icarus Dive.
Additional:
* Although 
Blood Rite can be easily avoided, if it does hit, its lengthy silence and pure damage can be a severe punishment for a slow, unobservant, or simply unfortunate Phoenix.
* His 
Rupture can turn Icarus Dive into a suicide option, and it cannot be dispelled, meaning even if Phoenix completes a Supernova, choosing to Dive may just cut its health back down.
* And finally, due to Phoenix's health costs, too much careless ability spamming may just put Phoenix into Bloodseeker's vision through 
Thirst, making it a very tempting ganking target.
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.
Phoenix
* Marci can destroy Supernova by herself with Unleash at any stage of the game.
* Phoenix is squishy hero with low armor and is very vulnerable for Rebound and Sidekick at the laning stage.
Phoenix
* 
Corrosive Skin gives Viper additional resistance to Phoenix's magical damage, and since they deal damage over time, Phoenix would be constantly afflicted by his passive's own debuff, making him not an ideal target for Phoenix's harassment. Phoenix's abilities also constantly drain its own health away, becoming more vulnerable to 
Poison Attack.
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.
Phoenix
* Phoenix constantly depletes its own health due to the health costs of its abilities. Unlike heroes that have a similar mechanic, Phoenix does not benefit from low health, nor does it really have a countermeasure for it. As such, Phoenix is a very vulnerable target for Necrophos to prey on, especially when caught off guard before it can cast Supernova.
Additional:
* Necrophos becomes a bigger threat the lower one's health gets, and unfortunately for Phoenix, most of its spells have noticeable health costs. Those costs, coupled with his 
Heartstopper Aura, means that staying in a teamfight for too long under Necrophos' presence will make Phoenix a more valid target for his ultimate, with its stun completely preventing any form of retaliation or protection. Necrophos players are also likely to buy more durability items such as 
Hood of Defiance, making him more able to withstand Phoenix's damage despite having no escape mechanisms.
* However, it is also important to remember that a Scepter-upgraded Supernova can help protect an ally from his ultimate.
Phoenix
* As a hero with uncommon traits, Phoenix's abilities require more health than mana. It is advised for Rubick to purchase health regeneration items such as 
Tranquil Boots, 
Urn of Shadows or Hood of Defiance to keep up with the HP loss.
* Phoenix's signature Supernova, if casted successfully, can turn a teamfight around if being stolen.
* The initial lift and the following crowd control from the drop of 
Telekinesis can protect the egg from being attacked if casted right before Supernova with quick fingers.
* A successfully reborn Supernova refreshes the cooldown of Telekinesis as well as 
Fade Bolt, so don't hesitate to spam both of them before Supernova with the reasons mentioned above.
* Supernova has a stun range of 1200, which requires Rubick to have Level 3 
Arcane Supremacy at least to exceed its range. Consider buying 
Aether Lens or 
Blink Dagger to help with positioning.
* It is not possible to cast Supernova (as of 7.31c) with Aghanim's Shard's extra Sun Ray even with both spell stolen, since Sun Ray takes up two stolen ability slots.
* Icarus Dive is a useful repositioning ability for scouting, initiation or escaping.
* Fire Spirits aids with Rubick farming given enough HP regeneration. In early skirmishes, the stolen ability can slow the attack speed of the enemy team to a crawl.
* Combined with Fade Bolt, both the attack damage and attack speed of the enemy team are reduced if they have no source of dispel, effectively nullifying their physical attack damage.
* Sun Ray thrives in and after a teamfight by damaging enemy heroes and healing allies at the same time.
* Rubick can interrupt both Icarus Dive and Sun Ray by casting Telekinesis.
Phoenix
* Although Phoenix has many ways to disable a Blink Dagger, the high cooldown of all of its spells makes them not as reliable for this. Also, its spells cost a lot of health to use, making it easy to get nuked down.
* Waning Rift prevents Phoenix from using Supernova to refresh itself, giving Puck's team time to finish it off, or allow Puck to burst Phoenix down.
* Dream Coil prevents Phoenix from using Icarus Dive without consequences. Waning Rift and Dream Coil are also able to cancel Sun Ray, which is its main source of damage in the late game.
Phoenix
* 
Lil' Shredder will make quick work of Supernova.
* 
Mortimer Kisses can easily hit a Phoenix using Sun Ray.
Phoenix
* Heroes with spell immunity-granting spells will render Phoenix useless against them, as Phoenix has almost no spell immunity-piercing ability, other than the stun at the end of Supernova: 
Lifestealer, Juggernaut.
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.
Phoenix
* Any hero with high attack speed will be a threat to Phoenix when it initiates, as they can easily tear down a Supernova, perhaps even while debuffed by Fire Spirits: Juggernaut, 
Clinkz, 
Troll Warlord, Beastmaster, Lina.
Phoenix
* 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.
Phoenix
* Any hero with high attack speed will be a threat to Phoenix when it initiates, as they can easily tear down a Supernova, perhaps even while debuffed by Fire Spirits: Juggernaut, Clinkz, Troll Warlord, Beastmaster, Lina.
Additional:
* Due to Fervor and Battle Trance, Troll Warlord is one of the best heroes to deal with Supernova.
Phoenix
* Heroes with blink or movement abilities, which are disabled by Pounce's leash: 
Anti-Mage, 
Earth Spirit, Faceless Void, 
Magnus, 
Mirana, 
Monkey King, 
Morphling, 
Pangolier, Phantom Assassin, Phoenix, Puck, 
Queen of Pain, Riki, 
Sand King, 
Spirit Breaker, 
Timbersaw, 
Tusk.
Skywrath Mage
* Once you get a Black King Bar, squishy spellcasters like 
Zeus, Skywrath Mage and others will be probably easy to deal with.
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.
Phoenix
* Phoenix's limit AoE, damage-over-time abilities give Io plenty of time to save allies with Relocate.
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.
Phoenix
* 
Song of the Siren does not affect Supernova, which allows her and her team to focus the egg while the enemy team is affected by sleep.
* Phoenix cannot use Icarus Dive for escaping when rooted by 
Ensnare.
* However, Phoenix has many area-of-effect abilities that allow him to clear Naga Siren's illusions from 
Mirror Image.
Phoenix
* Sand King and Phoenix have many tools to deal with multiple enemies at once, which will work well against a crowd of illusions.
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.
Phoenix
* Supernova allows Phoenix to save himself (or an ally, with 
Aghanim's Scepter) through 
Echo Slam. Earthshaker will also have a difficult time destroying the supernova, due to his low base attack time and poor agility.
* Icarus Dive can pass through Earthshaker's 
Fissure.
* Most of Phoenix's abilities disable Earthshaker's Blink Dagger for a good period of time due to the damage-over-time nature of its spells.
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.
Phoenix
* Phoenix's large damage over time with Icarus Dive and Fire Spirits can kill Chen's allies before he can use Hand of God.
* Phoenix naturally buys 
Spirit Vessel, which allows him to reduce healing from 
Divine Favor and 
Hand of God.
* Phoenix's Supernova cannot be damaged by Chen's creeps, and their normal speed means they will often not be able to kill Phoenix whenever he uses Supernova.
Additional:
* Not only Phoenix is able to disrupt Chen's jungling with Fire Spirits, but its high damage over time can also force Chen to use Hand of God prematurely, potentially wasting any chance to save his allies during teamfights.
* Creeps' damage and attack speed are very abysmal, so Chen often cannot kill Phoenix whenever it casts Supernova.
Skywrath Mage
* Heroes that can easily kill Faceless Void from outside his Cronosphere; 
Sniper, Skywrath Mage, etc.
Phoenix
* Fire Spirits does damage over time, preventing Faceless Void from backtracking the full damage with Time Walk.
* Fire Spirits applies a big attack speed slow, stopping Faceless Void from doing many attacks while in Chronosphere.
* Sun Ray can heal allies and damage Faceless Void from outside Chronosphere.
* Supernova can be cast outside of Chronosphere, forcing Faceless Void to step away from it, lest he'll take a lot of damage
Skywrath Mage
* Skywrath Mage's Mystic Flare can deal huge damage to Clockwerk inside his Power Cogs.
Phoenix
* Clockwerk being confined in his own Power Cogs means Clockwerk is unable to quickly escape from Phoenix's Sun Ray and Supernova.
* Sun Ray will also heal the enemy Clockwerk is fighting, making it unlikely for Clockwerk to take an enemy down with him.
* For the same reasons, Phoenix also makes a powerful ally for Clockwerk when the situation is reversed.
Skywrath Mage
* Mystic Flare can easily burst down Legion Commander while she is Dueling.
Phoenix
* Heroes who can hide the Dueled target (
Outworld Destroyer, 
Shadow Demon, Tusk, Phoenix with Aghanim's Scepter etc).
Additional:
* Legion Commander relies on her powerful attack and her 
Duel to be effective. But if Phoenix gets the jump on her first, she can find herself severely slowed, taking heavy damage, and find herself unable to Duel a burning Supernova.
* It must be noted that 
Press the Attack will both dispel the attack slow of Fire Spirits and grant her or whoever she targets bonus attack speed. This allows her to easily destroy a Supernova if caution is not taken to prevent this from occurring. As such, it would be a better decision to simply avoid a farmed or skilled Legion Commander instead of attempting to overpower her.
* If an ally is caught by Duel, Phoenix can use Sun Ray to heal the ally and damage Legion Commander, possibly swinging the Duel in their team's favor. Or with Aghanim's Scepter, Phoenix can save an ally from dying in Duel with Supernova and cancel the Duel as well.
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.
Phoenix
* Fire Spirits applies a severe attack speed slow, severely hindering Phantom Assassin's damage output.
* Phantom Assassin cannot cast Phantom Strike on Phoenix during Supernova.
Additional:
* While her Phantom Strike does give limited extra attack speed, she cannot use the ability against the Phoenix Sun, and while her 
Blur may protect her from attacks, Phoenix's strong magical DPS burns away her small health pool quickly, and the attack speed slow makes her unable to fight back (provided she has no source of spell immunity).
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.
Phoenix
* Lone druid's bear attacks on Phoenix's Supernova Egg don't increase the hit count. Given that Lone Druid's main hero often doesn't have much farm, the Supernova Egg is less likely to get killed.
Skywrath Mage
* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, 
Dark Willow, 
Enigma, 
Invoker, Pugna, Skywrath Mage, Tinker, Zeus, 
Oracle.
Phoenix
* Heroes with high health especially Strength heroes will take more damage on Sun Ray: 
Axe, 
Pudge, 
Bristleback, 
Mars.
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
* 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.
Phoenix
* Phoenix will usually be on the sidelines or further back ready to use Sun Ray. Even after Magnus successfully uses Reverse Polarity and skewer Phoenix's teammates, Phoenix can usually counter-initiate using all of its abilities.
Phoenix
* Fire Spirits greatly reduces Slardar's already low starting attack speed (which Bash of the Deep relies on), making the laning phase very hard for him and discouraging Slardar from aggressively threatening lane kills.
* Supernova, ignoring Phoenix's lack of armor and Slardar's high damage single hits, is extremely hard for Slardar to take down on his own, especially after being hit by Fire Spirits.
* Icarus Dive is one of the longest distance escape spells in the game, and can help a good Phoenix escape from Slardar before he gets a Blink Dagger. However, the high cooldown means Phoenix is vulnerable to backstabs from any roamers after said spell is used.
* Slardar can interrupt an Icarus Dive from completing the flight with both of his stuns, however, likely leading to death if Supernova is on cooldown.
* A lot of the items a Phoenix builds throughout the game naturally counter Slardar. 
Shiva's Guard, 
Heaven's Halberd and 
Eul's Scepter of Divinity all stall Slardar's normal attacks in some way, while Spirit Vessel's percentage-based damage is good against his innate durability.
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
* 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.
Phoenix
* Primal Beast is disarmed during Trample so will be unable to destroy a Supernova no matter how close it is to him.
* The same ability can also be used to save allies with the help of an Aghanim's Scepter.
* Sun Ray will do thousands of damage to Primal Beast if surviving a full channel time due to his high health scaling for the ability.
* Icarus Dive is a fantastic way to escape Primal Beast after he has used Onslaught.
* Phoenix has a naturally very high health pool making it hard for Primal Beast to deal with him with his magical damage.
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
* 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.
Phoenix
* Due to Spirit Breaker's low attack speed, Supernova is problematic for Spirit Breaker to take down, and even more so with Fire Spirits debuff applied.
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.
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.
Phoenix
* Since all of Phoenix's abilities (except for Supernova) have health costs, heroes like 
Ancient Apparition or Necrophos can turn Phoenix's abilities against it. However, Supernova does completely protect Phoenix from 
Ice Blast.
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.
Phoenix
* Icarus Dive helps Phoenix escape from Cold Feet.
* However, all of Pheonix's basic abilities do cost health, which can be harmful under the effects of Ice Blast.
* Supernova can save Phoenix from Ice Blast.
Additional:
* Supernova with or without Aghanim's Scepter allows to save ally or himself through Ice Blast.
* Icarus Dive quickly escapes from 
Cold Feet.
Phoenix
* Supernova negates Kunkka's combo entirely, as it can't be affected by spells while using Supernova.
* Icarus Dive also allows Phoenix to dodge Ghostship and Torrent.
Phoenix
* Icarus Dive quickly escapes from Shadow Demon abilities, especially 
Demonic Purge.
* Phoenix AoE abilities remove Shadow Demon's illusions created by 
Disruption.
Phoenix
* Sand King has nothing to deal with Supernova, as none of his spells are effective.
* The damage-over-time abilities of Phoenix disable Sand King's Blink Dagger very often.
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
* 
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.
Phoenix
* Sun Ray allows Phoenix to heal any allies caught in Berserker's Call while burning away Axe's high HP at the same time.
* Icarus Dive and Fire Spirits puts Axe's Blink Dagger on cooldown.
* Axe's slow attack speed makes it difficult for him to destroy Supernova on his own.
Phoenix
* Phoenix's Supernova cannot be damaged by Familiars.
* In the early and mid game, Sun Ray won't deal enough damage to be reduced by Gravekeeper's Cloak.
* Once Sun Ray deals enough damage to protect Visage, a layer of Gravekeeper's Cloak is burnt every 0.2 seconds.
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
* 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.
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
Phoenix
* Heroes with high health especially Strength heroes will take more damage on Sun Ray: Axe, Pudge, Bristleback, Mars.
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.
Phoenix
* Heroes that are able to slow Tiny's attack speed, like Tusk and Phoenix, will greatly limit his Physical damage output.
Phoenix
* Heroes with slow movement speeds and small health pools (supports like Crystal Maiden or Witch Doctor) are easy targets for Phoenix. Should they be inflicted by its DOT debuffs, they will be very quickly killed without even getting a chance to fight back.
Phoenix
* Heroes with high health especially Strength heroes will take more damage on Sun Ray: Axe, Pudge, Bristleback, Mars.
Phoenix
* Heroes who depend on attacks (such as 
Shadow Fiend or 
Drow Ranger) can be nullified by Fire Spirits' attack speed slow.
Phoenix
* Heroes with slow movement speeds and small health pools (supports like Crystal Maiden or Witch Doctor) are easy targets for Phoenix. Should they be inflicted by its DOT debuffs, they will be very quickly killed without even getting a chance to fight back.
Phoenix
* Phoenix with Supernova
* Heroes that can dodge Glimpse:
* Puck with 
Phase Shift
* Riki with 
Tricks of the Trade
* Phantom Lancer with 
Doppelganger
* Ember Spirit with 
Sleight of Fist and 
Activate Fire Remnant
* Chaos Knight with 
Phantasm
* 
Naga Siren with Mirror Image
* Tusk with 
Snowball
* Juggernaut with Omnislash
* 
Brewmaster with 
Primal Split
* Lifestealer with 
Infest
* Phoenix with Supernova
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
* 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.
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.
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.
Phoenix
* Phoenix's AoE abilities can prove troublesome for Phantom Lancer.
* Fire Spirits dramatically reduces Phantom Lancer and his illusions' attack speed.
* Icarus Dive's movement speed reduction makes retreating difficult.
* Supernova burns away illusions, and is invulnerable to attacks from illusions.
Skywrath Mage
* Skywrath Mage's very low health allows Monkey King to ambush and finish him off quickly.
Phoenix
* Icarus Dive and Supernova can destroy the tree Monkey King is standing on.
* Fire Spirits reduces Monkey King's attack speed, preventing Monkey King from building up Jingu Mastery.
* Supernova can be casted next to Wukong's Command, forcing Monkey King to step away of it or to withstand its massive AOE damage
Additional:
* Icarus Dive, Sun Ray, and Supernova all destroy trees that Monkey King relies on to use his ability 
Tree Dance. If you spot him, you can quickly Icarus Dive in his direction and then follow up with Fire Spirits and Supernova. If you manage to cut the tree he is on, he will be stunned for 4 seconds and will be forced to take a lot of damage. However, most Monkey King players tend to build attack speed items to make use of their passive, 
Jingu Mastery, so a battle against a farmed Monkey King will depend on who gets the jump on the other first.
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.
Phoenix
* Her Refraction charges can and will be easily burned away by Phoenix's damage over time abilities, and Meld can't protect her from Phoenix's AoE abilities, even without detection.
Additional:
* Phoenix's abilities target and deals damage over time, making them a threat against Meld and Refraction. His abilities' nature makes them pretty hard to correctly land on the target, but that is not a problem against a Templar Assassin that needs to stand still during Meld.
* Icarus Dive allows Phoenix to shrug off the slow from her trap and make an easy escape from her ambush.
* As Templar Assassin relies on her quality-over-quantity bursting attacks to make quick work on fragile target, Fire Spirits' attack speed reduction can cripple her ability to deals any damage during combat. With the debuff applied in early-mid game, a Meld-breaking hit from her is significantly slowed to the point that her target can travel a safe distance before she even lands the hit.
* Sun Ray has a quick damage tick and will burn through her Refraction in no time.
* Supernova deals damage over time in an incredibly large area, and again with her quality-over-quantity style, she may not be able to attack quickly enough to break through the Phoenix Sun by herself. (not to mention the debuff from Fire Spirits) This can lead to a failed ganking attempt or even a turnaround.
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.
Phoenix
* Heroes with strong area damage to destroy Phantasm illusions: Axe, Ember Spirit, 
Legion Commander, Phoenix
Skywrath Mage
* Heroes with a low health pool (Crystal Maiden, Skywrath Mage etc)
Phoenix
* Heroes who depend on attacks (such as Shadow Fiend or Drow Ranger) can be nullified by Fire Spirits' attack speed slow.
Phoenix
* Chemical Rage kills Phoenix very quickly in Supernova.
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.
Phoenix
* 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.
Phoenix
* Heroes with hiding abilities can protect disabled allies: Outworld Destroyer, Shadow Demon, Tusk, Phoenix with Aghanim's Scepter.
Phoenix
* Any hero with high attack speed will be a threat to Phoenix when it initiates, as they can easily tear down a Supernova, perhaps even while debuffed by Fire Spirits: Juggernaut, Clinkz, Troll Warlord, Beastmaster, Lina.
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.
Skywrath Mage
* Fate Edict can completely negate Skywrath Mage's heavy magic damage.
Ancient Seal.
* Fortune End dispels
Phoenix
* Phoenix does significant magic damage over time which can either be dispelled or negated by Fate's Edict.
* Oracle's burst damage potential can prove lethal to Phoenix, as they already have to sacrifice health to cast their basic skills.