Insanely solid entry! The concept is really good, the graphics are gorgeous, the level design is on point, the music is amazing AND dynamic, the sounds are really good, the theme is fitting... Honestly, that's awesome, I had a blast!
The two small little things that bother me a bit are that it is tedious to restart a level (just a "R" to reload would have been awesome =p) and having 2 keys to swap is a bit strange to me, I would have liked a single cycling key instead. But these are two really minor points, that's still one of the best entries I've tested so far, congrats!