About the Mashle Magic & Muscles Manga Volume 13

Right before the destined day of the eclipse, an army of demi-humans invade, throwing the land into chaos. Renatus and the other visionaries launch a counterattack, but they immediately find themselves face-to-face with Innocent Zero's four remaining sons. Later, after a crushing display of power, Innocent Zero demands the frightened populace hand the unconscious Mash over. Can Meliadoul find a way to recharge Mash in time for him to defend himself?