Kazuki Takahashi, creator of influential manga and trading card game Yu-Gi-Oh! was found dead off the coast of Okinawa alongside snorkeling gear on Wednesday, the Japan Coast Guard has announced via NHK. Takahashi died of unknown causes, and the circumstances around his death are currently being investigated. He was 60 years old.

Takahashi (born Kazuo Takahashi) began working as a manga artist (or manga-ka) in the early '80s but did not find mainstream success until 1996 with the debut of his series Yu-Gi-Oh!. Yu-Gi-Oh! tells the story of a young boy named Yugi Mutou, who solves an ancient puzzle which allows his body to be possessed by a mysterious ancient spirit whose presence begins to change Yugi's life through challenging foes to play the dangerous Shadow Games.

Yu-Gi-Oh! was originally serialized in the Shōnen magazine published by Shueisha titled Weekly Shōnen Jump. The manga was unique in the way that it featured different games within the story, which set up the path for the creation of the very successful Yu-Gi-Oh! trading card game, which became the top selling trading game in the Guinness World Records in 2009, and has, in its run sold tens of billions of cards. Yu-Gi-Oh was also adapted into two different anime, four films, and many different spinoffs.

Takahashi and his creation Yu-Gi-Oh! Have had a massive impact on the manga, anime, and gaming industries, and many of his fans are mourning his loss today and sharing the impact Takahashi's work has had on fans and the world of manga.