My idea for the light disk:
The handling would work just like Takato14's Z-Saber, where the disk will remain on your Blockhead's back when the disk is equipped. When you use left click, (Or whatever you have your attack key assigned as...) your Blockhead will both take the disk of its back and throw it. The disk will ricochet of walls, floors and ceilings, and after a few seconds, the disk will automaticly home into and return back to the thrower. The disk should also be a one-hit kill.