Really liked the design of your character, enemies and bosses. The idea of having to experiment with your build in order to complete levels is super interesting, but unfortunatelly didn't really work in this case - all the levels can be easily completed on the starting build with skill changed to ghost. The dash skill felt really useless, I didn't see any need to use it in any level.
The first boss fight was really entertaining, it was fun to learn its moveset and to come up with a good strategy againts him. I can't say the same about the second one - I simply camped at the highest platform and he barely attacked me, which is super underwhelming given how cool he looks :)
Overall, really liked the presentation - visuals, aesthetics, etc., but didn't really fall for the gameplay.