Kazuki Takahashi was widely-known for creating the manga comic series Yu-Gi-Oh! that became a global franchise. This included TV shows, films, books, toys, and a successful card game.
Now, the 60-year-old has been found dead in the sea in Japan.
The coastguard stated that Takahashi died during a snorkeling trip, close to southern Okinawa Island.
An official for the city of Nago added that he was located off the coast with an underwater mask, snorkel, and fins on.
“We are investigating the case as both a possible accident or crime,” he said.
Yu-Gi-Oh! means King of Games. It involves a spikey-haired teenager, Yugi, who gets an old puzzle that wakes up his alter ego which is an Egyptian Pharoah. He then solves problems by using games.
Between 1996 and 2004, it was published in the Japanese comic magazine, Shonen Jump. In 1999, it turned into a real card game.
10 years after that, the game became the best-selling trading card game in history named by the Guinness Book of World Records. This comes after 22 billion cards were sold.