Cardfight!! Vanguard - 4x11 - Season 4, Episode 11- Followmy.tv

After Serra creates the Millenium Blizzard Prison, Kamui begins his fight against him. He quickly deals a lot of damage to Serra while proclaiming that he will find Aichi. Serra taunts him by saying that Aichi does not want to be with Kamui and the others anymore. Serra triumphs over Kamui, which causes the prison to damage Kamui's body. Both Misaki and Kamui try to fight Rati and Serra again, but due to their injuries, the two Quatre Knights simply leave but not before Serra tells Kamui that the Quatre Knights must be defeated in order to reach Aichi. After Misaki and Kamui regroup, they decide to return to Card Capital and upgrade their decks. Meanwhile, Kai returns to Team Asteroid HQ along with Miwa and Naoki. They meet with Ren and ask about Aichi, but Ren again claims he does not remember him. However, when Kai mentions the Quatre Knights, Ren shows awareness about them, which makes Kai believe that Ren knows more than he is letting on. To find answers from Ren, Kai prepares to cardfight him.