Dive into a massive open-world ocean with no loading screens. Manage your oxygen, hunger, and thirst meters while exploring kelp forests, volcanic vents, and deep cave systems. Gather raw materials to fabricate diving gear, seamoths, prawn suits, and sprawling subsea habitats. Scan fragments to unlock blueprints. The non-linear progression lets you explore at your own pace.

Start by crafting a standard oxygen tank and fins immediately. Collect salt deposits and coral samples to make bleach for drinkable water. Cook fish instead of eating them raw to retain hydration. Scan every broken fragment you find near wrecks to unlock vehicle blueprints. Always monitor your depth rating before diving deeper with the seamoth. Build a small base early for storage and safety.

You crash-land alone on an alien ocean planet called 4546B. The vast underwater world teems with vibrant coral reefs, dark trenches, and terrifying leviathans. You must scavenge resources from the seafloor, craft tools and vehicles, build underwater bases, and slowly unravel the mystery behind the crash and the ancient alien structures scattered across the depths. Survival depends entirely on your wits.