Nice idea, solid execution. I like how useful dying is, the branching paths in level design, diffuculty slope balance, checkpoint system. Gravestone positioning could be adjusted if mid-air so you always can climb previous stone (now it's possible to die too high). Phrases ended at some point, I guess you could make them loop. And I'm not sure it's the most fitting music for the atmosphere, but it adds some juice. Overall good game, good job!