After I got teleported above the fist level - there was a bit of floor, one alien and no walls... I think it either bugged for me or it just ends here for now?
Stun gun didn't stun aliens, I think? Only was able to do the killing part...
Interesting idea of gun color being used for puzzles. Though had to read comments, since the first note didn't work for me.
Needs some work on, but base ideas, story and gameplay already there, so it can be an interesting twist with a shooter-crawler puzzle game!