* If Storm Spirit isn't careful, he could fall into a trap set by Techies and another hero acting as bait.
* Stasis Trap roots Storm Spirit for 2/3/4/5 seconds, which could be the end of Storm Spirit since he can't use Ball Lightning to escape.

* Any hero reliant of mobility, like Storm Spirit.

* 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).

* Luna has low HP, low range and often stalks through jungle. She cannot properly disarm Proximity Mines and could fall victim to their traps.
* Of course, if Luna happens to catch Techies off-guard, they won't be able to survive for long against Eclipse, Lucent Beam, and right-clicks.

* Techies is very good against roaming supports and gankers such as Bounty Hunter, Riki, Weaver, Earthshaker, Nyx Assassin, etc. that are constantly moving around the map.

* 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.

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

* Morphling usually has low max health due to shifting strength into agility, making him an easy target to blow up.

* 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.

* Proximity Mines and Stasis Traps can be placed near trees to detect Monkey King.
* Follow up with Blast Off! to destroy the tree, causing Monkey King to take high damage, fall from the tree, and become stunned.
Additional:
* Techies can turn his tree jumping ability against him, by placing Proximity Mines/Stasis Traps that will detect him near trees, and then destroying the trees around him with Blast Off!, stunning him and dealing high damage, on top of him being silenced when the stun expires.
* Monkey King's mobility is also severely limited around Techies' mines as he will almost always trigger them due to the cooldown time between tree jumps. Monkey King will be forced to take mine damage or escape with Primal Spring.

* 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 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.

* After using Snowball, Tusk can't control where he's going, allowing Techies to make him roll into mines.

* Stasis Trap's root prevents Earth Spirit from using Rolling Boulder to escape.

* 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.

* A common playstyle among Tinkers is to teleport to a lane creep using Boots of Travel and immediately blink into the trees to cast March of the Machines. If Techies can predict where said Tinker would blink after teleporting, he could place strategic Proximity Mines or even Remote Mines in those places. Stasis Traps also prevent Tinker from blinking or teleporting away.

* 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.

* 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.

* 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.

* 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.

* 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.

* 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.

* 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.

* 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

* Techies is very good against roaming supports and gankers such as Bounty Hunter, Riki, Weaver, Earthshaker, Nyx Assassin, etc. that are constantly moving around the map.

* Techies is very good against roaming supports and gankers such as Bounty Hunter, Riki, Weaver, Earthshaker, Nyx Assassin, etc. that are constantly moving around the map.

* Techies is very good against roaming supports and gankers such as Bounty Hunter, Riki, Weaver, Earthshaker, Nyx Assassin, etc. that are constantly moving around the map.

* 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.

* 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.

* In general, heroes that provide vision will see Dark Rift coming: Techies, Templar Assassin, Treant Protector

* Ember Spirit relies on his Fire Remnant to keep a steady push and then retreat to a safe distance. Keeping two or three patches of Remote Mines on a lane will severely impair him from pushing that lane without risking his life.

* Due to the nature of Divided We Stand and the playstyle of splitting up multiple Meepos across the map, Techies can limit Meepo's movement with mines forcing the Meepo player to either keep all Meepos together or be extra careful when moving each individual Meepo because clones cannot carry any True Sight-providing item.
* However, if a mine blast isn't enough to kill a Meepo, he can Poof to safety of another Meepo.
Additional:
* Stasis Trap can lock multiple Meepos in place and prevent them from Poofing.
* Proximity Mines, Remote Mines and Blast Off! can deal heavy magic damage to multiple Meepos.

* Well planted Proximity Mines can lure Bloodseeker to his death during ganking attempts.

* Heroes with damage burst can often kill Chen or his allies before he can use Hand of God: Lina, Techies, Shadow Fiend, Pugna, Nyx Assassin.

* 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.

* 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.

* 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.

* 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.

* 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.

* 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.