This is pretty good for your second game! I think boss rush games are pretty cool and I like your execution. Each boss felt unique and I liked having different options for attacking, each weapon also being pretty unique. I've noticed there's a boss rush jam coming up if you're looking for more jams to join ^̮^. One thing I'll suggest though is adding more game feel and feedback. As InvalidSpacebar said it could really use some audio. SFX will help sell impacts and make players more aware of when they take or deal damage. Things like particle effects, screen shake, hitstop, etc. will also really help here.