Small pieces of metal attached to the wall hold a piece of glass. The glass can either be pointing left or right, depending on its position. The glass is white for regular mirrors and orange for orange glass mirrors.
Two types of mirrors are introduced in the Test Subject series: regular mirrors introduced in Test Subject Blue, and orange glass mirrors introduced in Test Subject Green.
Referred simply as just mirrors, Regular mirrors, are rare interactive objects introduced late in the game Test Subject Blue, but appearing a lot throughout these levels. Regular mirrors will deflect, and only deflect, both Blue's Proto-Suit bullets and orange enzyme bullets.
Mirrors are usually placed so that the bullet they deflect will be shot into another mirror, and so on. When first introduced, mirrors are used for deflecting orange enzyme bullets and bringing them to places previously unreachable. They are still used for that purpose in other levels of Test Subject Blue but are later used for puzzle solving.
If an orange enzyme bullet and blue enzyme bullet meet when being deflected, they will simply pass each other. Mirrors will flash white when a bullet touches the mirror, along with making a clicking sound. Mirrors can also deflect laser beams from lasers.
Mirrors appear in Test Subject Arena in levels 3, 5, and 10 to 13. Some can be rotated in some levels.
Mirrors also appear in Test Subject Complete but only in level 2, used to reflect a laser beam under a gap as the first hazard. They can also deflect Rex209 bullets if one intentionally fire one at a mirror during the invincibility right after respawning nearby.[GIF needed, rewording appreciated]
Orange glass mirrors
A variation of mirror introduced in Test Subject Green is the orange glass mirrors. The player can rotate orange glass mirrors by activating a switch button. Other than being rotatable, they act exactly as regular mirrors.
- The mirrors in Test Subject Blue bear a strong resemblance to rotating mirrors in the game Canary. Coincidentally, Canary was the game released before Test Subject Blue.