The seas rose and the surface is gone. What's left of us holds on in hab-shells: salvaged homes anchored in the dark, overgrown by a sea that moves into anything warm that stays still. Every fathom takes something back.

One dive, one shell

You raid a shell in a short deckbuilding run. Fight through its chambers, and at each extraction point choose whether to surface with what you've got or push deeper for a richer haul. At the core waits the Pressure-Heart; crack it for the full harvest. The shells you dive are generated enemy bases, each one read by the faction that built it.

Three ways to dive

The solo dives are the heart of the game. Open Descent is the main run, generated shells set to the Pressure you choose. Daily Signal is one shared shell, the same for every diver that day. Endless Descent drops the floor and lets the Pressure climb until you break, once you've earned the way down.

Build a shell others raid

Between dives you build your own shell and lay out its defenses. While you're offline, real divers raid it, and you read the report when you surface. Climb a ranked seasonal ladder against players in your range. The rivals you face are real divers.

Pick your answer to the drowning

Four factions, four answers to the rising water, and you belong to one. The Hold seals its shell and outlasts everything, betting the water climbs forever. The Stilled live inside a dead leviathan's carcass and call it holy. The Bellows holds the last working air plant and rules by the leash, all railguns and harpoons. The Severed lost their crew and trust the swarm and the open water. Every faction draws on the Flotsam pool, the cast-off divers' common gear.