Kazuki Takahashi, the creator of the international smash hit manga and trading card game Yu-Gi-Oh!, was found dead in Okinawa, the Japan Coast Guard said Thursday. He was 60.

His body was discovered Wednesday floating off the coast of Nago in the southern prefecture. Takahashi was traveling alone in Nago, a popular vacation destination, and had apparently been snorkeling when he died from unknown causes, a coast guard spokesperson said.

Kazuo Takahashi was born Oct. 4, 1961, and began working as a manga artist in the early 1980s. But it was not until 1996 that he began his rise to international fame with the story of a spiky-haired boy who challenges his enemies to duels involving magical games.