Who counters Mira in Rainbow Six Siege?

Ash, Ace, Hibana, Maverick and Thermite. Ash: Breaks the Black Mirror. Ace: S.E.L.M.A. destroys the mirror if its blast touches it. Hibana: pellets on the reinforced wall destroy the mirror. Breaks the Black Mirror.

Who pairs well with Mira?

Castle: Mirrors and barricades. Rook: Armored anchor. Azami: Mirror and Kiba. Clash: Shield and mirror.

Mira: counters, combos and tips

Q: What is Mira's gadget?

Black Mirror. Two one-way bulletproof windows punched into reinforced or soft walls; the canister on the defender side can be broken to drop the glass and open a murder hole.

Defender · Viperstrike · anchor, site intel

Mira is countered by Ash (breaks the Black Mirror), Ace and Hibana. Mira pairs best with Castle, Rook and Azami.

Mira's gadget: Black Mirror

Two one-way bulletproof windows punched into reinforced or soft walls; the canister on the defender side can be broken to drop the glass and open a murder hole.

Who counters Mira?

AshHard counterBreaks the Black Mirror.
AceStrongS.E.L.M.A. destroys the mirror if its blast touches it.
HibanaStrongpellets on the reinforced wall destroy the mirror. Breaks the Black Mirror.
MaverickStrongtorches the anchors or the canister from below.
ThermiteStrongburning the wall the mirror sits on removes it.
TwitchStrongdarts break the canister when the drone is on the defender side. Breaks the Black Mirror.
KaliSituationalLV Lance through the wall destroys the mirror.

What does Mira counter?

Mira isn't a direct counter to any one operator; the value is in the role.

Best Mira combos

CastleMirrors and barricades.
RookArmored anchor.
AzamiMirror and Kiba.
ClashShield and mirror.
KaidHold the site together.
AruniHold the site together. Strongest on Oregon.
SmokeHold the site together.
BanditHold the site together.

Where Mira is strong

Strong pick on Oregon. Sites: Oregon Kids' Dorms / Dorms Main Hall, Oregon Dining Hall / Kitchen, Oregon Kitchen / Meeting Hall, Oregon Laundry Room / Supply Room.
Broken Mira window gives an angle on planters, hard to counter. Sites: Border Armory Lockers / Archives.
Mirrors in Supply Closet and Freezer stop a backside take. Sites: Oregon Laundry Room / Supply Room.
Reinforce right side for a bunker; mirror peeks from there. Sites: Kafe Dostoyevsky Cocktail Lounge / Bar.
Strong anchor on Bank. Sites: Bank Lockers / CCTV Room, Bank Staff Room / Open Area, Bank Tellers' Office / Archives, Bank Executive Lounge / CEO Office.
Mirror on the box helps hold the Armory side. Sites: Border Supply Room / Customs Inspection.

Mira myths

Flores breaks Mira's Black Mirror. The wiki states the RCE-RATERO explosion does not affect the Black Mirror. The sim's mirror-breaker list includes flores; remove it.
Brava breaks Mira's Black Mirror. The Black Mirror is not a hackable gadget for the Kludge (FIXED; keep it out).
Ash / Zofia always break a Mira. Only when the mirror is on a soft wall; on a reinforced wall breaching rounds and impacts do nothing to it. The sim lists both as unconditional breakers.
Thermite opens a Mira before the push (disputed). TRUE when Thermite burns the reinforced wall the mirror is on: it destroys the mirror.

Key Mira facts (Y11S3)

Mira deploys 2 Black Mirrors (5 s) on breakable or reinforced walls; one-way and bulletproof; a canister on the deployed (defender) side ejects the glass after 4 s when destroyed. (since Y2S1, current)
A single melee hit from either side shatters the Black Mirror and blocks all sight through it (the window is not removed; it can still be ejected). (since Y6S2 (patch 6.2.0))
Hard breachers destroy a mirror on a reinforced wall: Thermite, Hibana and Ace's S.E.L.M.A. (Ace since Y6S1.3) break it; Maverick can torch the four corner anchors or cut a hole under it and shoot the canister. (since Ace: patch 6.1.3 (May 2021))
Twitch's Shock Drone darts and Zero's Argus lasers can destroy the canister, opening the mirror, but only with a view of the defender side where the canister sits.
Kali's LV Lance destroys Black Mirrors (it destroys gadgets on both sides of the wall it pierces).
Flores's RCE-RATERO explosion does not affect the Black Mirror. (since current wiki text)
Brava's Kludge cannot hack a Black Mirror: it is not on the list of hackable defender gadgets (it isn't electronic).
On a non-reinforced wall, anything that destroys the wall around the mirror removes it: Ash's breaching rounds, Zofia's impacts, soft breaches. Usually it sits on a reinforced wall, where these do nothing.
Flashes (Blitz, Ying, stun grenades) still blind defenders through the glass.

Sources

More defenders

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