Viz Edition Release Date: February 3, 2009
Proper Japanese Title: 無敵城塞
A trip to the school festival at rival Ojo High gives Sena and the Devil Bats a rare chance to unwind, but their visit is more than just friendly. Will Hiruma succeed in learning the identity of Ojo's latest and greatest secret weapon? Meanwhile, Doburoku introduces a new training method designed to keep Deimon in top form and improve all the players' stamina, but they'll need more than breath control if they hope to stand a chance against the White Knights!