Oh look, it's the last minute power up trope where their "real power" comes back.... Partially...
Let me guess, either some time during the fight or at the end of it, Lufasu will lose that extra power and essentially go "back to sleep" isn't it.
@monkey123 As far as we know. Still possible to have happened in between chapters, though considering how much time they spend with everyone else... Not much alone time.