Blind, der Dieb

This boss is a chore to make appear, but once the fight starts it is simple. Blind moves left and right along the top or bottom of the room, firing lasers and fireballs. Dodge them and slash at the head, its weak spot. After enough damage the head comes off, but a new one grows back after a while, so attack that one. It is safer to strike from above Blind. Fight with the Cane of Byrna running and it goes down easily.