Ruuga Kaizu is a character in Cardfight!! Vanguard G and Cardfight!! Vanguard: Shinemon Arc. He was first introduced in Cardfight!! Vanguard G: Z. He was diffridden by Valeos, one of the Apostles and the user of the Magallanica Zeroth Dragon, Zeroth Dragon of Distant Sea, Megiddo. In Shinemon Arc he's part of Team Dragon's Vanity, a special team assembled by Esuka Hibino to participate in the S-Cup with the objective of defeating Shinemon and Team Capital. He has a history with Rive Shindou. (Source: Cardfight!! Vanguard Wiki)