The Octoliths are large crystals that are required to power the Alimbic Cannon. They only appear in Metroid Prime Hunters. The Alimbics created them as a power source, but when their civilization was ruined, they hid each of the eight Octoliths inside the Infinity Void by using teleporters. This means that Gorea, along with the Oubliette, cannot be accessed without all eight Octoliths. Samus gathers the Octoliths in order to destroy Gorea, but the other bounty hunters also attempt to gather them to claim the "Ultimate Power." If Samus faints while fighting another hunter, she will lose one Octolith and will be forced to retrieve it. In order to keep Gorea contained, the Alimbics put their best defenses around the Octoliths, but Samus still manages to obtain them all. Whenever one is collected, Samus recieves a telepathic message, most likely from the Alimbic spirits she meets at the end of the game.
- The Ocoliths are similar to Metroid Prime's Artifacts and Echoes' Sky Temple Keys in the manner that they must be retrieved to fight their respective games' final boss.