Gundam Build Fighters (2013)

S01E20 Aila's Betrayal

Fellini advances to the quarterfinals, where his opponent turns out to be Aila—a revelation that shocks Sei and Reiji as they finally learn who she truly is. With the Team Nemesis Chairman now present, Aila feels immense pressure to claim victory, as he has vowed to give the championship trophy to his grandson as a birthday gift.