Day — Salvage. The tide brings wrecks to the shore. Hold interact beside one to pull out oil, timber, glass and brass. Your satchel is small: walk back to the lighthouse door to drop off what you carry. The tide rises all day and floods the shallows, so work quickly.
Night — Keep the light. The lamp's beam is your eyes, and it burns oil. Hold the beam on a ship until its ring fills and it turns for the harbour. Ships left in the dark drift onto the rocks. Arrows on the screen edge point to ships out of view, with the seconds left before they reach the rocks; they turn ember when time is short. A dashed arc marks how far the beam reaches. Fog shortens it, and a narrow beam reaches further and burns less. Gloomlings crawl out of the water to drain your lamp. Strike them, or let the beam burn them away. If the lamp runs dry, hold interact at the door to pour in stored oil.
Settings. Reduce motion (no shake, flicker or flashes) and High contrast are on the title and pause menus, and are remembered.
Between nights. Spend what you salvaged on upgrades. They work by themselves from the next night; tap a row to see exactly what it does. The survivors you rescue stay by the hearth and help: the Hearth tab adds it all up. Last through seven nights. The seventh brings the Last Ship.