Mako Tsunami, known as Ryota Kajiki (梶木漁太 Kajiki Ryōta) in the Japanese version, is a character in the video game, Yu-Gi-Oh! Dungeon Dice Monsters. He is based on Ryota Kajiki from the Yu-Gi-Oh! manga.
A seafaring specialist turn dice player. He participates in tournaments so that he may buy a sonar-equipped boat with his winnings.