Cute game! I actually like the art, it's simple but effective. Would look so much nicer if every sprite had the same pixel scale.
My main issue is with collisions. Getting stopped on every collision made the game unnecessarily frustrating to play. This is especially apparent on trees, since they have a huge hitbox.
Night time is fun and chaotic, although I lost pretty much immediately. Well that's on me for being bad at tower defense games ^^'
Good job, keep it up!