Cardfight!! Vanguard: Legion Mate-hen

Synopsis

As the trapped trio of Kai, Gaillard, and Naoki learn of Serra's true colors, Kourin arrives to find that Serra has frozen the seals containing Aichi, who awakens while covered in a dark aura. Kourin tries to check on Aichi, who blasts her away with an energy pulse and knocks her unconscious. Serra further reveals his true plan to release the certain power that is inside Aichi. Serra then moves on to the next stage of his plan, which is tricking Neve into fighting Aichi.

Meanwhile, Gaillard tells Kai and Naoki the reason why Aichi was sealed to begin with. As it turns out, a "seed" was planted inside Aichi's body during the final battle in the Link Joker invasion. This seed is Link Joker, which was slowly taking control of Aichi. Believing that the only way to deal with the seed was to contain it, Aichi gathered Gaillard, Neve, Serra, and Rati as Quatre Knights and had them seal himself away along with the seed. With Kai and Naoki now knowing the truth, they form an alliance with a reluctant Gaillard. Although still injured from his fight with Kai, Gaillard tries to use his flame powers to melt their ice prison. At the same time, Neve cardfights against Aichi, who is now using a Link Joker deck.

(Source: Wikipedia)