Heilig Feuer

Heiliges Feuer (神聖滅火の手 (ホーリーファイア), Hairihhi Faia; German for "Holy Fire", Japanese for "Sacred Destruction Flames") is a special technique of the Quincy.

Overview
The, and later, the Impero Nascosto, possess this unique capability that allows them the ability of creating blue flames, which is simply condensed reishi. It is powerful enough to set fire to the rocks and sand of Hueco Mundo, that usually cant burn.