This game is really fun, and i really enjoyed it, so here is some feedback :)
- The actions are great but sometimes attacking feels clunky specially when trying to turn and attack or perform any action.
- Bosses are great, a little basic but still pretty fun to play, would love to see more patterns in the future :)
- The upgrade system is good, probably i would add more upgrades to it, more variation.
- Sometimes the bosses instantly kill you, i dont know if thats the desired effect or not.
- Make the attacks more distinguishable, or add a queue so the player knows that they are going to perform an attack.
- A final note, 2 hit points is kinda crazy to deal with, specially without a way to refilling health without spending an upgrade point.
Great game, i will follow you and keep an eye in your work in the future! :)