* 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.

* A well-timed Global Silence prevents Dazzle from saving allies with Shallow Grave or Shadow Wave. Items that could dispel the silence are expensive, and difficult for Dazzle to farm from a support role.
* Arcane Curse and Last Word cause long damage over time, which may outlast Shallow Grave.

* While many of Silencer's spells are a great steal for Rubick, Silencer effectively neuters Rubick's excellent counter-initiation potential thanks to Global Silence.
* Rubick's relatively low intelligence for such a heavy caster means that losing Intelligence to Intelligence Steal will make your mana pool even smaller.

* 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.

* Global Silence takes Omniknight out of the fight completely.
* Glaives of Wisdom are a great harass vs Omniknight during the laning stages of the game, since it doesn't aggro creeps & ignores his high base armor. It deals pure damage, which means it can also go through Guardian Angel.
* Silencer's intelligence steal can also cause Omniknight to falter in the early phases as it reduces his ability to use his spells.

* 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.

* Crystal Maiden is squishy, is heavily spell reliant, has low base Intelligence, and is naturally slow, making her an ideal target for Silencer
* Crystal Maiden's Freezing Field has a similar cooldown to Global Silence, therefore, Freezing Field can almost always be canceled to ruin aggressive Crystal Maiden initiations.

* 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.

* As Tinker relies heavily on his spells to be effective, Last Word and Global Silence will render him largely useless.
* Arcane Curse effectively prevents Tinker from casting spells during its duration, as he will otherwise suffer heavy damage.
* Glaives of Wisdom deal pure damage, which make quick work of fragile heroes like Tinker.
Additional:
* Silencer can stop Rearm, preventing Tinker from spamming his abilities/items or escaping.

* 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.

* Silencer burns easily through her effective hp from Mana Shield, by taking away her int.
* Arcane Curse punishes her repeatedly casting Mystic Snake to keep her mana pool high. Can force her to use Manta Style before he has casted Global Silence and Medusa usually does not want to build Black King Bar.

* 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.

* Heroes that have long silences, such as Night Stalker and Silencer, will prevent Abaddon from saving his allies effectively and disable the active component of Borrowed Time.

* 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.

* Silencer's Intelligence Steal can reduce Storm Spirit's damage output if he gets some kills on laning phase.
* Last Word and Global Silence will make Storm Spirit an easy target.
* Global Silence can be used to block Storm Spirit from connecting abilities after a Ball Lightning on his targets.

* Any hero reliant of mobility, like Storm Spirit.

* 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.

* Arcane Curse punishes Necrophos if tries to spam Death Pulse, increasing the duration of the slow and damage taken over time.
* Last Word heavily damages Necrophos and also silence him for a lenghty duration.
* Glaives of Wisdom will reduce temporarily Necrophos intelligence on each hit dealing hindering his ability to spam Death Pulse, also reducing his attack damage and mana pool; dealing increasing amounts of phisical and pure damage each time. Silencer will permanently steal Necrophos intelligence if killed by him or dies nears him.
* Global Silence turns Necrophos almost useless for a long time, allowing your team to easily dispatch him, since he heavily relies on his spells to survive.

* Heroes with summons like Broodmother,Enigma, Invoker, Nature's Prophet, Lycan, Visage;or illusions, like Naga Siren, Phantom Lancer, Terrorblade are effective at keeping the choke points and rune spawns safe from Proximity mines in the early game.

* In general, heroes such as Lion, Silencer, Skywrath Mage, Sven, Ogre Magi and others with reliable disables are crucial to killing Techies before they can suicide.

* Naga Siren with Mirror Image
* 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

* Heroes with silences : Bloodseeker, Riki, Silencer.

* 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.

* Arcane Curse stacks every time Bristleback uses an ability, forcing him to stop spamming his abilities, or take heavy health degeneration.
* Glaives of Wisdom's pure damage cuts through Bristleback's tanky items. also steals intelligence both permanently and temporarily and cause mana issues for Bristleback
* Last Word and Global Silence stops Bristleback from using his abilities altogether.
Additional:
* Glaives of Wisdom deals pure damage, therefore it is not reduced by Bristleback.
* Bristleback will not be able to cast Viscous Nasal Goo or Quill Spray while silenced, effectively blocking a major part of the hero's damage and preventing Warpath charges from stacking.
* Arcane Curse slows Bristleback down and lasts longer the more abilities he uses. On the other hand, if he doesn't use any abilitiess, he will begin to lose Warpath charges.

* Shadow Demon's main source of damage is his low cooldown, high damage spells - meaning Last Word and Global Silence will pretty much take him out of the game for the duration.
* Shadow Demon likes to spam his abilities, which makes him vulnerable to Arcane Curse.
* If Shadow Demon dies near Silencer, he will lose intelligence, reducing his mana pool, mana regen and attack damage. Furthermore, if the game is long and Shadow Demon dies often, the intelligence losses will also reduce his spell damage.

* Kunkka relies on his powerful AOE spells to turn the tides of teamfights. He cannot use them while silenced.
* Last Word can mess up Kunkka's ability synergy, silencing him in the middle of his strong combo.
* Global Silence can disable Kunkka's spell casting from anywhere on the map, even if Kunkka is spell immune at the time.

* Generally strong against every spellcaster, Puck fully relies on their skill set and is barely a threat when silenced.
* Arcane Curse disables Blink Dagger for quite some time, and is also effective against Puck as he tend to use his spells a lot.
* Glaives of Wisdom can do a lot of damage against Puck due to Puck's low agility gain and armor.
* Last Word can prevent Puck from getting his full combo off, limiting his effectiveness in team fights or ganks.
* Global Silence can take Puck out of fights entirely.

* Like any hero with a channeled spell, Last Word is a counter to it.
* Global Silence goes through spell immunity and prevents Witch Doctor from casting his spells.

* Arcane Curse discourages Lina from using her abilities, preventing her from building up Fiery Soul stacks.
* Last Word and Global Silence are great against Lina for the same reason, as well as interrupting her combos and preventing her from casting spells.

* 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.

* Invoker is heavily dependent on his spells, making him useless during Global Silence, as well as interrupting Invoker during his combo.
* Arcane Curse is particularly deadly, because Invoker will continuously lose health if he keeps invoking and casting new spells.
* Last Word will silence Invoker when he casts Invoke, interrupting his combo.

* 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.

* Heroes with pure damage can kill Huskar when he inevitably gets low on health: Outworld Devourer, Silencer.

* Last Word and Arcane Curse have the range to hit Dark Willow beyond Bramble Maze.
* Global Silence renders Dark Willow useless in teamfights.

* Arcane Curse can effectively discourage Undying from casting his spammable abilities in a team fight, as Undying will have to suffer more damage and the slow due to the penalty duration of Arcane Curse.
* Last Word and Global Silence are able to silence Undying for up to 6 seconds, preventing Undying from gaining strength and healing his ally or himself.

* Silencer can easily ruin Enigma's initiation, as Global Silence cancels Black Hole, even through Black King Bar and Linken's Sphere.
Additional:
* Last Word can be cast from a long range to prevent Enigma's potential initiation.
* Global Silence can interrupt Enigma's Black Hole channeling through Black King Bar and Linken's Sphere.

* Because Warlock's abilities are all active abilities, Silencer can make his impact minimal.
* Arcane Curse prevents Warlock from using his abilities without taking 56/84/112/140 damage, and slowed by 9%/12%/15%/18%.
* Last Word can prevent Warlock from casting his combo.
* Global Silence can nullify Warlock's impact in fights and prevent him from getting any spells off.

* 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.

* Heroes with silencing abilities that are not blocked by Linken's Sphere, like Puck's Waning Rift, Death Prophet's Silence or Silencer's Global Silence.

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

* 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.

* Basically, Heroes that heavily rely on abilities for damage or escape, such as Queen of Pain and Storm Spirit.

* 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.

* Silences and other types of lockdown that prevent Weaver from using his spells: Silencer, Riki, Lion, Legion Commander, Shadow Shaman, Bane.

* With 4 active abilities, Shadow Shaman is weak against silencing foes such as silencer, Drow Ranger and Death Prophet.

* 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).

* Windranger heavily relies on her abilities for any form of tactical advantage and damage. A well timed silence will make her useless: Puck,Silencer, Death Prophet, Skywrath Mage, Drow Ranger, Earth Spirit, Grimstroke.

Additional:
* Silencer's abilities hamper Windranger's effectiveness in battle, preventing her from comboing abilities and escaping using Windrun.

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

* 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.

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

* Heroes with abilities or items that can silence or disable Anti-Mage for long periods of time will prevent him from Blinking away: Silencer, Shadow Shaman, Death Prophet, Clinkz, Riki, Broodmother, Skywrath Mage, Puck

* Heroes with silences and hard stuns such as Doom, Silencer, and Lion can keep Mirana from Leaping away.

* Arcane Curse punishes Grimstroke for spamming Stroke of Fate.
* Global Silence takes Grimstroke out of team fights entirely.

* Global Silence and Last Word can prevent Ember Spirit from casting Activate Fire Remnant to escape.
* Glaives of Wisdom also provide high pure damage that is not negated by Flame Guard.
* Arcane Curse is also a potent harassing tool in the laning stage as its cooldown is lower than Flame Guard's.

* 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.

* 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.

* Silencer's Last Word and Global Silence prevents Jakiro from casting any spell.
* A carry Silencer can easily take down a support Jakiro with his Glaives of Wisdom.

* Pugna is very reliant on his abilities for damage. (Just be careful around the Nether Ward)

* Both Arcane Curse and Last Word punishes casters with spammable spells such as Sand King.
* As a strength caster, Intelligence Steal reduces Sand King's mana pool even more.
* Global Silence silences Sand King, effectively reducing Sand King's initiation and counter-initiation potential. It can also interrupt channeling of Epicenter.

* 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.

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

* Silencer's intelligence steal will heavily reduce Outworld Devourer's damage output, if Outworld Devourer dies a lot near/to Silencer.
* Global Silence and Last Words will render Outworld Devourer helpless unless he has dispelling item/ally.
Additional:
* Silencer's Intelligence Steal will heavily reduce Outworld Devourer's damage output, particularly from Sanity's Eclipse.
* Last Word and Global Silence will take Outworld Devourer out of the fight unless he has built Black King Bar.

* 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

* 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.

* 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.

* Global Silence stops Snapfire's Mortimer Kisses.
* Last Word can prevent Snapfire from casting additional spells.

* Arcane Curse deals repeated stacks of damage to Timbersaw because he relies on constantly using his abilities.
* Glaives of Wisdom deals pure damage and when cast manually, nearby creeps will not attack silencer, making it an effective harassment tool.
* Although Last Word takes a while to trigger, it will break Timbersaw's ability combo and can be used to silence him.
* Global Silence will silence Timberaw no matter where he is on the map. This can be used to help allies get a kill on him, or prevent Timbersaw from killing someone.
Additional:
* Timbersaw is heavily reliant on his abilities for damage and escape, allowing Silencer to effectively disable him and make him useless in both team fights and 1v1 scenarios.

* 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.

* Oracle's reliance on spamming his spells can be easily hindered by Silencer's Arcane Curse.
* Last Word and Global Silence negates Oracle's attempt to save his allies with his spells.
* Fate's Edict is useless against Glaives of Wisdom's pure damage.

* 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.

* Silencer's Global Silence will render Zeus useless for 6 seconds in a team fight.
* Arcane Curse will punish Zeus for casting spells, which can cause continuous damage to him should he continue to cast spells.
* Last Word can silence Zeus and prevent him from spamming his spells.
* Silencer often builds Orchid Malevolence (or Bloodthorn) which can be used on spell casters like Zeus, forcing him to invest in a Linken's Sphere.
Additional:
* Zeus' main source of damage is his low cooldown, high damage spells - meaning Last Word and Global Silence will pretty much take him out of the game for the duration.
* Zeus likes to spam his abilities, which makes him vulnerable to Arcane Curse.
* If Zeus dies near Silencer, he will lose intelligence, reducing his mana pool, mana regen and attack damage. Furthermore, if the game is long and Zeus dies often, the intelligence losses will also reduce his spell damage.