My take on Ash's design
I had this idea that as his blood (whatever it is - liquid crying obsidian, maybe?) touches his skin, it immediately burns into it and permanently turns it into solid obsidian. So the more injured he gets, the more of his body turns to stone and in a way, the stronger he becomes.
But not quite.
Obsidian limits his movements, and also he's lost his vision in the affected eye. So one thing in exchange for another, except he never bargained for his condition
