Really nice idea to have new levels all 10 seconds. At first I was expecting that for each level before the boss you gather "strength" for the actual boss fight and not only for the next level so I was a bit confused. The boss fight itself was really amazing. It felt super rewarding with the "No hits taken" mechanic that the player gets a buff as a reward for not being hit by the boss. The levels in the boss fight itself were a really smart idea as the player can regain health and increase the odds of defeating the boss. Sadly even after several tries I did not manage to get past the first boss so maybe a checkpoint at half the health of the boss for noobs like me would have been nice ^^.
Graphics are minimalistic but also very clean so I liked the looks. Audio was fitting even though maybe the music was a bit silent. The SFX fit perfectly. Had fun playing, good job!