Reactor Core (Frigate Orpheon)

The Reactor Core appears in Metroid Prime. When Samus Aran first enters the Reactor Core on the Orpheon, she battles the Parasite Queen. Later on in the game, after acquiring the Gravity Suit, she finds the Reactor Core underwater due to the frigate crash.

Inhabitants

 * Several dead Space Pirates, killed by a Parasite Queen. Found before Orpheon crashed.
 * Parasite Queen, found before Orpheon crashed
 * Aqua Pirates, found after Orpheon crashed