Dark Grenchlers are Grenchlers possessed by the Ing. At close range, Dark Grenchlers will attack by biting or ramming. At distant targets, they can fire energy beams. Samus can damage them by firing at the shell-covered nerve center on their backs. Samus encounters them in Dark Torvus Bog. They bear resemblance to the 2D Metroid games' Hornoad and Prime's Baby Sheegoth, sharing the latter's weak area.
- Main article: Grapple Guardian
- "Darkling-possessed amphibious predator. Symbiosis brings additional power to creature, but it retains its key weakness. Target the back shell to reveal a weak spot.
Darklings are drawn to possess vicious predators, making the Grenchler a prime candidate. Despite the added toughness gained from possession, the Dark Grenchler retains its one weakness. Remove the back shell with explosive blasts to expose its pain center, then attack the pain center to quickly dispatch the creature." — Logbook "Dark Grenchler" (Metroid Prime 2: Echoes)