Lucifer and the Biscuit Hammer Vol. 9-10 (manga)

The final battle to save the world...so they can destroy it. With only one of Animus golems left to fight, the Beast Knights are hard at work mastering the technique Yukimachi and Subaru have devised. But Yuuhi has other training to do: he needs to be able to defeat his friends in combat once Animus is out of the way, to allow Samidare his Lucifer to fulfill her dream of smashing the planet herself!