i like this game
you can tell the amount of effort put into it. soooo many animations and backgrounds. plus all the levels and the level designs, the balancing and the enemies. not to mention so many different bosses.
it's a fun game, the glitches didn't do anything that stunted me or held me back so i don't really care about that. there could be a bit more atmosphere shift between the terrain foreground and the background. I notice you outline a lot in black. When there's a background object outlined in black AND a walkable object outlined in black, it can be a bit confusing at times but the levels were simple enough that it didn't give me too much trouble.
the level 5 boss is pretty hard in my opinion, i couldn't pass that point, but nevertheless, i had fun playing it. good control scheme too, i like that