Fragor

is a technique used by Sōsuke Aizen in his Final Hōgyoku Fusion.

Description
Forming a bluish-purple sphere of energy in one of the mouths on the top of his wings, Aizen launching it toward his target. Upon impact, the sphere explodes with enough force to create a large crater and releases a shockwave which can be felt miles away from the blast site. It left Ichigo Kurosaki with a heavily burnt arm.