I can say without a doubt that this is one of the greatest games I have ever played. It accomplishes an aesthetic that mimics the RPGs and platformers of old, but stands on its own as a unique work, much the way Cave Story did.
The boss battles are challenging and well-made, the graphics are top-notch, and the music is fitting. At first I didn't care for the soundtrack, but as the game goes on and the story unfolds, it gets better and better. And the graphics are simply amazing in the Mul Cave, and I get the sense that both the music and the graphics were arranged to get better and better in step with the story arc, to give that feel of increasing awe and gravitas. This game is a masterpiece, and I am sorry that I rated so many things so highly in the past, if only because it detracts from the full marks I give you now. Congratulations!