Theres a solid core idea here! The level art design is great, and your character and enemy sprites look really good! Though the objective didn't seem intuitive. I wasnt sure initially if I needed to be attacking the Knights, just avoiding them, or really what initially. I also very much did not realize that the yellow objects weren't just walls blocking the path but things you needed to pick up and very much would not have guessed to place them on a cracked block.
Maybe adding an intro level where you need to pick up a Nobel and place them on a Cracked Block with text telling you how to do so would have helped a lot before getting thrown into the game. Though once the player figures that out (and that there is a jump button) it's an enjoyable experience. Again, the core idea is really solid!