The third season of Cardfight!! Vanguard: overDress.

Teen runaway, Yu-yu, whose empathy is matched only by his inability to say no to others, meets Megumi Okura. Megumi invites him to a mysterious destination, Dreamland Wonder Hill amusement park. There, he discovers intensely competitive groups like Team Blackout gather to play an exhilarating and alluring game called Vanguard. Yu-yu is drawn into this world of high stakes competition where he must balance new friendships against his drive for victory.

(Source: Sentai Filmworks)

Watch Cardfight!! Vanguard: will+Dress (Dub) Online