Alright, i played the game again, i didn't really understood how it worked at first. I like the idea of stunning enemies instead of getting rid of them, the sprites you did also look really nice, reminds me of those gameboy games! The suggestions i have are to maybe make the stun gun stun instantly, the first time i played i wasn't sure if the gun was doing anything, and make the player be able to stun upwards and downwards, it will improve the experience by a lot! I also noticed that you could move with the arrow keys, but it was a bit messy since you couldn't push the boxes that way(it is a minor issue however).
Other than this, i think you made a fun concept here, keep it up! <3