A species native to Tallon IV, these passive creatures are virtually indestructible and can only be removed when the surface they are climbing on is destroyed. They block Samus's progress in the Sun Tower and also in the Tower of Light, where she acquires the Wavebuster.
- "Wall-crawler that generates electrical pulses. The Oculus exposes its single eye when active. The electrical field that covers it is enough to deter most predators. If the Oculus detects anything capable of presenting a real threat, it retracts into its impermeable shell." — Logbook "Oculus" (Metroid Prime)