Kurosaki Ichigo is able to transform this form after his training with Uruhara. His personality greatly changes and so does his power.The only side effect is his hollow form as an evil alter ego. He later is able to use a mask that gives him the same power as his hollow form but without the side effect. He can only maintain this power for 11 seconds.
Hollow Ichigo is a pimp and bitch at the same time.