Dark Visor

From Wikitroid, the Metroid wiki

The Dark Visor is one of the two visors exclusive to Metroid Prime 2: Echoes, the other being the Echo Visor. The Dark Visor allows Samus Aran to see interdimensionally between Aether and Dark Aether, and makes it easier to see in the poisonous atmosphere in Dark Aether. It also highlights enemies in red, making them easier to locate in poor-visibility environments. It can also reveal interdimensional objects and Seeker-Missile locks. You receive it after beating Chykka.