* Just like Batrider, his Ball Lightning can be used clear Nature's Prophet's treants and easily destroys Sprout.
* Electric Vortex prevents Nature's Prophet's escaping from Teleportation.

* Naga Siren is a natural split-pusher. With a Radiance equipped, she will easily out-push Nature's Prophet, farming his treants in the process.
* Ensnare prevents Teleportation. Even if he hid inside Sprout, Song of the Siren lasts long enough to prevent him from escaping.
Additional:
* Naga Siren is a natural split-pusher. With Rip Tide, she will easily out-push Nature's Prophet, farming his treants in the process.
* Ensnare prevents Teleportation. Even if he hides inside Sprout, Song of the Siren lasts long enough to prevent him from escaping.

* Sniper is very squishy and cannot deal with heroes that jump onto him and lock him down. Storm Spirit closes the gap in a fight against Sniper, and Sniper has no way to escape except for some items.
* Storm Spirit can dodge Assassinate with a correctly timed Ball Lightning.
Additional:
* Storm Spirit can close the distance towards Sniper very easily with his ultimate Ball Lightning.

* Ensnare with her attacks allows Naga Siren to gank Sniper easily.
* Rip Tide removes Sniper's very little armor.

* Ball Lightning allows Storm Spirit to escape through Viper Strike, wasting Viper's mana.
* It's also very easy to wait out the duration of Nethertoxin's break until Viper picks the level 25 silence talent.

* Naga Siren can easily disjoint, and dispel Corrosive Skin with Mirror Image.
* Since Viper is a single-target hero, he will not stand a chance against Naga Siren because she is an illusion based hero.

* Storm Spirit can hunt down Arc Warden with his Ball Lightning and kill him quickly due to his lack of escape abilities.
* None of his abilities are effective against Storm Spirit, as they can be evaded with Ball Lightning.

* Song of the Siren stops him from acting and her illusions can push better than him because Mirror Image has a longer duration.
* Arc Warden does not often build Radiance, which is useful for illusions and countering illusion pushes.
* Mirror Image dispels Flux or prevents Flux's slow.
Additional:
* Her illusions can push better than Arc Warden's Tempest Double because Mirror Image has a longer duration.
* Mirror Image dispels Flux, and the illusions stop Flux from working.

* Storm Spirit destroys trees and ignores impassable terrains with Ball Lightning, rendering them dangerous places for Tinker to hide within.
* Ball Lightning disjoints projectile from Heat-Seeking Missile and damage from March of the Machines.
* Electric Vortex prevents Tinker from teleporting away, and Static Remnant and Overload can easily burst him down.
Additional:
* He can easily catch Tinker in the trees with Ball Lightning and kill him with Orchid Malevolence and his abilities, which deal both physical and magical damage, making them difficult for Tinker to itemize against.

* Illusion heroes, such as Naga Siren, Phantom Lancer, Chaos Knight, Terrorblade will become strong against Tinker in the late game when Tinker's only area of effect damage, March of the Machines, ceases to kill illusions quickly. Without Aghanim's Scepter Tinker is forced to defensively disarm heroes with Laser, leaving illusions free to deal physical damage which Tinker's low armor makes highly effective. In addition, Mjollnir or Battle Fury, two common pickups against illusion heroes, don't work well on Tinker at all.

* Escape-type carries: Slark, Storm Spirit, Weaver.

* Heroes that create illusions (such as Spectre, Shadow Demon, Phantom Lancer, Naga Siren, Chaos Knight, Terrorblade) or bring other units into the fight (such as Nature's Prophet, Lone Druid, Chen, Enchantress and the aforementioned Meepo and Arc Warden) can cause Eclipse to strike the illusions/summons unintentionally. (However, in many cases Moon Glaives can resolve this issue and eliminate them before activating Eclipse).

* Naga Siren with Mirror Image
* Heroes that can remove the Track debuff with their skills:
* Abaddon with Aphotic Shield and Borrowed Time
* Huskar with Life Break
* Juggernaut with Blade Fury
* Legion Commander with Press the Attack
* Lifestealer with Rage and Infest
* Naga Siren with Mirror Image
* Omniknight with Heavenly Grace
* Oracle with Fortune's End and False Promise
* Phantom Lancer with Doppelganger
* Slark with Dark Pact
* Ursa with Enrage
* Weaver with Time Lapse
* Tidehunter with Kraken Shell when damage received reaches the threshold.

Additional:
* Bounty Hunter is a single target dealer, so he will not fare well against Naga Siren. He might as well try to Track her, but her Mirror Image will dispel the effect. Also, Ensnare reveals invisible units while they're rooted, putting Bounty Hunter in a tricky situation.

* Heroes that are naturally hard to gank, ranging from beefy tanks like Abaddon and Wraith King to heroes with quick escape mechanisms like Anti-Mage and Storm Spirit are also undesirable targets for a lone, roaming Bounty Hunter to scout out and initiate on.

* Illusion-based heroes are effective against Omnislash and Juggernaut's single-targeted damage: Naga Siren, Chaos Knight, Terrorblade,Phantom Lancer.

* Heroes with escaping and disjointing abilities can be good against Juggernaut: Riki, Queen of Pain, Puck, Storm Spirit, Ember Spirit, Slark etc.

* Ball Lightning allows Storm Spirit to destroy a large amount of trees, negating Tree Dance. It also makes it easy to avoid Wukong's Command and Boundless Strike.
Additional:
* Ball Lightning allows Storm Spirit to easily catch up to Monkey King, destroying a large number of trees, cancelling Tree Dance, and causing Monkey King to be stunned in the process.

* Terrorblade has low mobility, which makes it easy for Storm Spirit to kite him.
* Terrorblade gains a lot of agility and gains very low strength, which makes it easy to burst him down with Storm's magical damage.
* All of Terrorblade's abilities are easily avoided by Storm Spirit as he can simply use Ball Lightning, wasting the duration of Metamorphosis, Conjure Image, and Reflection.
* However, if Storm Spirit's Orchid Malevolence is on cooldown or if he doesn't have it, Terrorblade can easily use Sunder and kill a careless Storm Spirit.
Additional:
* Storm Spirit heavy magic damage bypass Terroblade high armor.
* Ball Lightning can either use to initiates Terroblade from distance or kite Terroblade from using Sunder as he has no source of disable to deal with Storm Spirit.

* Ball Lightning with or without the Static Remnant talent allows Storm Spirit to destroy Phantom Lancer's illusions quickly. It is also easy to dodge Spirit Lance with Ball Lightning and makes Spirit Storm very hard to catch even with Phantom Rush.
Additional:
* Ball Lightning destroys illusions, avoids Spirit Lance, and makes Storm Spirit very hard to catch, even with Phantom Rush.

* Storm Spirit can steal Aegis of the Immortal during Roshan attempts through the Pit, because of his Ball Lightning.
* Ursa has no way to catch a slippery Storm Spirit, as Earthshock's slow will do nothing to stop Storm Spirit from using Ball Lightning.

* Mirror Image's illusions can easily walk straight at Dazzle and attack him, due to Dazzle's lack of reliable AoE nukes or disables.
* Ensnare roots Dazzle or his allies, making it harder to stay range of Dazzle's saving abilities.
* Song of the Siren can be used to initiate a fight with superior positioning, potentially zoning Dazzle's high-impact spells out of the fight.

* Song of the Siren is very difficult for Rubick to Spell Steal when he is affected by sleep.
* Ensnare and Rip Tide together with some attacks can take Rubick down quickly, due to his low health pool and armor.
* Naga Siren usually buys Diffusal Blade, which will prevent Rubick from spamming his abilities from Spell Steal.
* Mirror Image allows to dodge the incoming stun from Telekinesis (when she is not a target) and it can also to dodge and dispel Fade Bolt's damage reduction debuff.

* Song of the Siren completely wastes Abaddon Borrowed Time while keeping him in place.
* Naga Siren is able to simply dispel Abaddon's Curse of Avernus with Mirror Image before getting hit 4 times consecutively.
* Although Naga Siren's illusions can be easily destroyed by Aphotic Shield, Naga Siren can resolve that issue easily by purchasing Heart of Tarrasque to drastically increase her tankiness. Plus, the said item makes Naga Siren harder to be distinguished from her illusions.

* 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.
Additional:
* 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.

* Song of the Siren can be used to nullify the effects of Winter's Curse, and when upgraded with Aghanim's Scepter it also outmatches the heal of Cold Embrace.
* If Winter Wyvern is reckless enough to put an ally in Cold Embrace, Naga Siren will be able to use her Ensnare to extend the disable on the hero affected by Cold Embrace.

* Ancient Apparition's only skill to stop Storm Spirit is Cold Feet, which is bad in general when trying to stop a Storm Spirit without any other disable.
* As a fragile support with low Strength gain and no magic resistance, Ancient Apparition is vulnerable to Storm Spirit's combos.

* Ball Lightning breaks Static Link.
* Razor has no way to catch a slippery Storm Spirit.

* Song of the Siren can be used to time out Guardian Angel, giving Naga Siren's team an easy opportunity to counter-initiate.
Additional:
* Song of the Siren will waste Guardian Angel.
* Ensnare fully works on Heavenly Graced targets. However, Ensnare is dispellable with any dispel, and so can be dispelled by Heavenly Grace.
* As an agility hero that relies on illusions, Naga is one of the most natural Diffusal Blade carriers, the bane of every hero with a small mana pool.

* Ball Lightning allows Storm Spirit to close the gap between him and Weaver in no time. Once locked down with certain items, Weaver is extremely fragile to Storm Spirit and his teammates.

* Ensnare is good vs bear.
* In teamfights, song of the siren may be used to properly set up and coordinate an attack on Lone Druid in the backline, bursting him down, allowing to completely ignore the bear.
* Druid lack innate AoE capabilities giving him no good way of dealing with illusions.

* Mirror Image can cause Huskar to Life Break the wrong target.
* Rip Tide reduces Huskar's already low armor.
* Song of the Siren allows teams to recover from Huskar's initiation, as well as the damage over time from Burning Spears.

* Mirror Image can dispel Frostbite.
* Song of the Siren can stop Freezing Field regardless of any kind of invisibility as well as allow Naga Siren's team to quickly close the gap on Crystal Maiden.
Additional:
* Mirror Image can dispel Frostbite.
* Ensnare and Song of the Siren can stop Freezing Field.
* Song of the Siren can allow her team to quickly close the gap on Crystal Maiden.

* Ball Lightning allow Storm Spirit to bypass Bramble Maze, and zip back into battle if he gets hit by Terrorize.

* Using Ball Lightning with proper timing, Storm Spirit can protect himself from Malefice's instances, disjoint Demonic Conversion's attack projectiles, get out of Midnight Pulse's radius or even dodge a Black Hole.
* An isolated Enigma in the early game can be easily killed by Storm Spirit thanks his higher mobility and dueling potential. However, Storm Spirit can be killed when caught by Enigma's full combo, especially if Enigma has Black King Bar.
* Storm can kill all of Enigma's Eidolons relatively quickly without much risk, slowing down Enigma's farming speed, preventing him from split pushing, and giving Storm its considerable bounty- especially if Enigma chooses the Level 25 Talent that gives him more Eidelons.

* Ball Lightning is the ultimate counter to Spectre's entire toolkit. With this ability, he can score easy kills on Spectre without her having any means of escape early game, kite her and her Haunt illusions when it's later in the game due to her having no form of pseudo-blinks. Furthermore, it is very difficult for Spectre to deal any substantial damage against Storm Spirit with Desolate, and without both a Manta Style and a Diffusal Blade he will always remain on the move. Also, Ball Lightning grants invulnerability, and as Storm Spirit likes to spam that ability, he can mitigate the damage done from Dispersion and Radiance.
Additional:
* Storm Spirit can exploit every one of Spectre's weaknesses, and thus is one of the best counters against her.
* Spectre has to be in melee range to deal damage, making her likely to trigger Static Remnants and susceptible to being kited by Overload procs.
* Electric Vortex can lock Spectre down as she doesn't like to build Black King Bar.
* Ball Lightning gives Storm Spirit multiple advantages:
* Spectre cannot evade Storm Spirit, as Ball Lightning is superior to Spectral Dagger in terms of mobility.
* Storm Spirit can kite her and her Haunt illusions when it's later in the game due to her having no form of pseudo-blinks (Reality is far inferior to Ball Lightning).
* It is very difficult for Spectre to deal any substantial damage against Storm Spirit with Desolate. Ball Lightning grants invulnerability and can mitigate damage done from Dispersion and Radiance.

* Ball Lightning disjoints an incoming Magic Missile, avoids Wave Of Terror, and allows Storm Spirit to easily escape if he ever gets Nether Swapped.

* Ball Lightning and Electric Vortex will catch Broodmother before she has a chance to retreat, and is able to catch her through the trees.
* Conversely, Ball Lightning also allows him to easily escape Broodmother, as she has no way to prevent him from using it before getting Orchid Malevolence.

* Heroes with teleports to escape Will-O-Wisp: Phantom Assassin, Puck, Queen of Pain, Storm Spirit

* Squishy heroes or heroes without hard disables or silences: Shadow Demon, Shadow Fiend, Venomancer, Ancient Apparition etc.

Additional:
* Shadow Demon will find a hard time catching a Storm Spirit, as he can get away with Ball Lightning.
* Static Remnant will make quick work of the spawned illusions from Disruption.
* With very high mobility and usually paired with Orchid Malevolence, he can catch Shadow Demon with ease both in ganks and in teamfights if Shadow Demon has no survivability items.

* Heroes with illusions: Chaos Knight, Naga Siren, Phantom Lancer

* Heroes that build Diffusal Blade or can fit it well into their item build will also make Medusa much less tanky: Riki, Naga Siren, Terrorblade, Juggernaut, Spectre, Slark,Drow Ranger.

* Illusion and heroes with summons are difficult to kill with Chen's single-target offensive spells: Terrorblade, Phantom Lancer, Chaos Knight, Broodmother, Naga Siren, Lycan, Visage. However, Chen can convert enemy summons with Holy Persuasion, as long as they don't bunch up.

Additional:
* Naga Siren can make landing Chen's combo very hard due to her being an illusion hero.
* Ensnare will prevent Chen from activating Hand of God.

* Heroes with considerable mobility can easily escape from a rolling Pangolier: Anti-Mage, Queen of Pain, Void Spirit, Storm Spirit, Ember Spirit, Earth Spirit, moreover, if a player is familiar with how Rolling Thunder work, they can adjust their movement to avoid it entirely and of course outplay the Pangolier player.

* Heroes with powerful rooting abilities will disable most of Pangolier's skill, a bonus point if it pierce spell immunity since it will also be able to stop Pangolier during his Rolling Thunder: Treant Protector, Meepo, Crystal Maiden, Dark Willow, Underlord, Naga Siren

* Squishy heroes or heroes without hard disables or silences: Shadow Demon, Shadow Fiend, Venomancer, Ancient Apparition etc.

* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Heroes that can quickly deal damage to her, regardless of how weak they are, can easily break through her Refraction:
* Multiple attackers thanks to summoned units or clones: Meepo, Witch Doctor, Lycan, Enigma, Shadow Shaman
* Multiple attackers thanks to illusions: Phantom Lancer, Chaos Knight, Naga Siren (bonus for her Ensnare). Also despite the visual effects, Templar Assassin does not spill damage against illusions or buildings, so she is not a really good hero to clean up illusions.
* Weak damage but high tick rate or persist in a long time: Slark, Gyrocopter, Queen of Pain, Shadow Shaman (Shackles), Pugna

Additional:
* Ensnare disables Lanaya's invisibility and Blink Dagger (a core item on Templar Assassin), and her illusions will break Refraction easily.

* Illusion-based and multi-unit heroes can take advantage of Chaos Knight's lack of area damage: Naga Siren, Phantom Lancer, Meepo, Broodmother

* Lycan is a carrier built entirely with physical attacks, having 0 AoE presence and no spell power. Due to this, he can't deal with illusions or Naga Siren's Ensnare.

* Illusion heroes like the aforementioned Phantom Lancer or Naga Siren, or heroes that tend to buy Manta Style, like Luna or Juggernaut, will give Slardar a hard time, as his damage is single-targeted.

* Heroes with summons and illusions such as Broodmother and Naga Siren, are ill-suited for Wraith King to fight, as he has no source of waveclear.

* Squishy heroes or heroes without hard disables or silences: Shadow Demon, Shadow Fiend, Venomancer, Ancient Apparition etc.

* Heroes that have superior mobility that can easily catch up with Mirana even after she used Leap to escape: Anti-Mage, Queen of Pain, Storm Spirit, Riki.

* In the early to mid game, Invoker is defenseless against Storm Spirit's ganking with Ball Lightning and Orchid Malevolence.

* Song of the Siren lasts long enough to prevent a successful Duel (but only if Naga wasn't the target).

* Storm Spirit is invulnerable during Ball Lightning, rendering Rupture ineffective against him.
Additional:
* Storm Spirit is invulnerable during Ball Lightning, allowing him to zip away from any ganking attempts with Rupture.
* Ball Lightning also prevents Bloodseeker from chasing down an injured Storm Spirit, or catching him in Blood Rite.

* Heroes with mobility spells can quickly escape from Stroke of Fate or break out of Soulbind: Anti-Mage, Queen of Pain, Morphling, Storm Spirit

* Heroes that rely on their high mobility such as Queen of Pain, Slark and Weaver can be constantly engaged against due to your excellent ability to chase over any terrain. Make sure you carry true sight items (such as Dust of Appearance or Gem of True Sight) for invisible heroes that could potentially escape your clutches.

* 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.

* Ball Lightning makes Storm Spirit a target difficult to chase, even for a hero as mobile as Timbersaw.
* The magical damage from Static Remnant and Overload together with Storm Spirit's high mobility allows Storm Spirit to jump on Timbersaw and burst him down, even if he tries to escape.

* Heroes that usually builds Linken's Sphere as a core item: Weaver, Medusa, Morphling, Queen of Pain, Storm Spirit

* Heroes with AoE abilities are a bane to Beastmaster's summons: Storm Spirit, Magnus, Pangolier.

* Mirror Image can be effective since Night Stalker cannot withstand fighting Illusions. If he's unable to tell which Naga Siren is real, he will have a hard time landing his Void and Crippling Fear.
Additional:
* Ensnare and Song of the Siren prevents Night Stalker from escaping and ganking during daytime or even nighttime.
* Rip Tide reduces Night Stalker's armor, making him easier to focus down.
* Mirror Image can be effective against Night Stalker, due to his single target abilities.

* Illusions make it difficult for Necrophos to target his Reaper's Scythe correctly, thus giving illusion heroes like Chaos Knight or Naga Siren an edge against Necrophos.