The basic tubular base compartment. Configurable size (short, medium, long, T-junction, X-junction). Accessed via Hatch — you cannot enter a base without at least one Hatch on a Corridor or Room exterior face.

Unlike Subnautica 1, SN2 has no structural integrity system — you can build Corridors at any depth without hull reinforcement. This is a major quality-of-life change that lets you commit to deep-base footprints (Power Plant, Root Canyon) without staging.