The art is this game was great! Really nicely done. If anything maybe a tad too many particles but I'm just being nitpicky.
The gameplay itself was nice, you made a pretty satisfying platformer. The camera was maybe a little too bouncy for me, especially when lining myself up for a jump with short movements. Reading the comments, it looks like I missed a secret gun so I had to kill the boss with the pistol!
Overall this game had a really great aesthetic, palette, and animations. A great entry to the jam, well done.