Metroid Cavern is a room on Phaaze in Metroid Prime 3: Corruption. The room is quite large, featuring two sections, the largest of which contains Phazon Metroids, hence the name. The first part features an unreachable hive containing infinitely spawning Phazon Metroids, while the second part has Phazon Hoppers emerging from burrows on the ceiling. The areas are blocked off by a creature acting as an organic barrier. To destroy it, Samus must shoot at its five antennae when they open, giving a clear shot at the main optical organ. When in the second part, the exit of the room is blocked off by a large Phazon mass, which explodes when enough Phazon Hoppers are defeated. After that, three Phaz-Ing appear.