Metroid Database Bestiary

An immobile organism that's entirely composed of ocular tissue. The Eyon is capable of launching sustained energy beams when active. However, the Eyon is sensitive to light and will close shut if a bright flash ignites nearby.

When you first encounter Eyons they cannot be killed, just temporarily disabled. It's actually easier to just run past them if you encounter many in a tunnel throughout the Chozo Ruins. Later, after you receive the Charge Beam, you can destroy them with a fully charged shot.

This creature is very similar to Beamos from The Legend of Zelda. In Metroid Prime 2: Echoes, the creature returns, but it's called Corrupted Sentreye. Eyons were security devices used by the Chozo, but they have a limited lifespan; in some areas of the Chozo Ruins, you can find petrified Eyons.