Die Perlen des Poseidon is a visual search game built around shapes that are hard to spot at first and lead to equally hidden treasures. A submarine expedition has found Poseidon's tomb, and somewhere inside lie the pearls of Poseidon.

Players take turns scanning the seabed with a stamp. Their treasure maps show strange objects that point the way to the pearls, and anyone who recognizes them knows where to look and can work out the magical names of the treasures. The player who finds the most pearls and names them correctly collects the most Poseidon thalers and wins.