I liked this game! The sprite work was very cute, and the boss fights had interesting mechanics that made them feel unique.
I think what I liked the most about this was the powerup system. It feels very roguelite-ish and made you consider your options before each fight. It would be cool if this powerup system was built upon, such as having them stack if you picked the same abilities as previous runs. For example, picking Adrenaline may increase the timer from 3 to 6 seconds!
The designs were also something I admired. The first boss was my favorite because of how well-themed it was.
This game has a lot of potential so I would love to see this developed!