The Things We Lost in the Flood, by Dean Moynihan
This is a game about loss, discovery, and creation. You're sailing through a flooded world—a flood caused by a tap opening in the Atlantic Ocean that "never really stopped." Drifting by ruins and ravaged buildings, your goal is to make sense of what happened to the world. While exploring the lost world, you also discover notes which other players have left in the world, you can also leave notes for other players.