An Octroll's size makes it nearly as large as Samus Aran. These cephalopods' attack pattern is nearly identical to that of the Chute Leech, though the former can jump much higher and cause more damage. Two of their tentacles possess fins, possibly used to float through the air. When destroyed, they nearly always yield large energy units.
The game's commercial depicts an Octroll rising from a blue liquid substance. In-game they thrive in the hazardous liquid. Since Metroid: Samus Returns depicts the hazardous liquid as purple, it is possible that the commercial intended to accurately depict the hazardous liquid, rather than water or some other substance.
- Metroid II manual
- "When Samus comes close, they fall fluttering downward."
- It is unknown if they became X Parasite hosts, as Samus did not encounter any Octroll-X in Metroid Fusion.
- Octrolls do not appear in Metroid: Samus Returns, though the Chute Leech appears in some of the same places that the Octrolls did in the original game.