Shortly after Yukio left for a mission, a blackout occurred at their dorm and the same Naberius appeared again.
In general, he is often the first one to try and make people feel better if they're down.
He succeeds in completely scorching the Impure King from Assiah with a blinding explosion of light, and sending waves of brilliant, bright blue flames down the mountain, burning everything that had been contaminated and destroying all of the bacteria.
He then sets his body on fire, scaring everyone except himself and Shiemi, who says that the flames are not hot but warm.