Time has passed, and the members of Team TRY3 have gone their separate ways as they enter high school. Tokoha is studying abroad in France, Shion is attending Fukuhara High, and Chrono enrolls in Tokyo Metropolitan Harumi High School. However, Chrono has a hard time adjusting to his new school life. Later, while working at Card Capital 2, Chrono is challenged to a cardfight by a peculiar young man, who soundly defeats him with his Nubatama deck. Before leaving, the man reveals his name to Chrono: Kazumi Onimaru. Upon learning that Kazumi is the reigning "Under 20" Vanguard champion, Chrono decides to enter the U20 Championship.