Game File: 

avandal.zip

ok not actually a shooter but I'm submitting this anyway because I'm late on the ideas I was working on. It has a laser at any rate.

I made this in five minutes exclusively because I wanted to take that screenshot.

Then I went back to add an ending and it took me about half an hour because it kept crashing the game so I was forced to put it in a different frame.

anyway...

Draw on the moon with a laser.

Left click turns the laser on, right click turns it off (couldn't get it to work when mapped to the same button). Space clears your drawing.