User blog comment:B214/Question and Answers 4/@comment-1.53.56.192-20141201134929/@comment-24098614-20141201231447

The power that Gasper used in the fight against the Khaos Brigade to fight the user of the Anhiliation Maker was similar to the power that was used by Alucard in Hellsing, and no wonder Rias was scared about that power.