Each player pilots her own submarine trying to spot the most underwater species and the largest coral reef, sending scuba-divers after forgotten treasures, collecting precious crystals to upgrade their ship and to escape the fearsome kraken's gaze...
Each submarine is divided into five parts, each of them independently upgradable from level 1 to level 3 and each one of them controlling a different ability of the player (however, there are no different abilities from one player to another). As there are multiple ways to score points and multiple takes on the submarine-upgrading order, the game offers several ways to win. The whole game takes mere 15 turns, each one of them simultaneous between all players, which makes it a fairly quick family game.
Even though the submarines have the same abilities game-wise, each looks differently, and a special attention was obviously given also to the depiction of marine life.