Slaughter Mode

is a technique used by Ururu Tsumugiya.

Description
Ururu Tsumugiya is able to sense unusual Reiatsu around her. If she senses danger from the source, such as an Arrancar she will react to it and automatically go on the offensive and attack them. This reaction can occur when she is sleeping, causing her to sleepwalk with the aim of eliminating those she perceives as a threat to herself and those around her. When this happens, the pupils of her eyes dilate unnaturally and her features are expressionless.