You never place a building here. A tribe walks across an island and settles three hearths by itself; your only tool is a hand from the sky that scoops up sand, water or lava and pours it somewhere else. Then a wave comes in from the south, and whatever ridge you heaped up is the town wall.

The first island takes a few minutes. After it there is the rising sea: the towns you keep grow, every wave lifts the water for good, you tap a town to walk its people uphill before the sea cuts them off, and the score is everyone who reaches the altar on the ridge. The sea changes every day.

It is free in the browser and plays on a phone, no account. A question for people who play city builders: did the flood feel fair, and what should a second island throw at your towns?