This mob spawns at +122, +1, +65 inside Velektor's castle. Go the north exit, there is a ramp at both sides. It pops on the top of the ramp. Also spawns at neg 28, pos 144, pos 7. Upon entering the castle, you go left and it's inside that first door on the left. A 3rd spot at just inside castle in the room on the right. -35, -160, +5.