The room cannot be entered until Samus has the Power Bombs as the room is blocked from both exits by Yellow Hatches. As for the room itself, the Putrid Alcove has a pool of Dark Water in its center (likely the origin for its name), with a Dark Phlogus in it. To one side of the pool is a wall made of Denzium that conceals a Power Bomb Expansion behind it. The room contains five Ingsphere Caches.
- Dark Phlogus
- "Morphology: Phlogus
- Aquatic carnivorous plant.
- Incredibly resillient. Target its vulnerable nerve center when it opens its mouth to attack; direct hits will stun target."
- Power Bomb Expansion
- Destroy the Denzium wall next to the pool.
- Ingsphere Cache
- "Morphology: Ingsphere Cache
- Living storage units of the Ing Horde.
- The Ingsphere keeps useful items in a dimentional pocket. The pocket can be breached by destroying the Ingsphere."
- Denzium wall
- "Structural analysis complete.
Block is composed of Denzium.
The local creatures have weakened it, along with time and erosion."