There’s also the whole issue of necromancy. Psionics may take center stage, but undead play a huge role in Athas. I could see necromancy getting a great deal of advancement in the Dead Lands. The curious detail imo is if necromancy is defiling/preserving or if it draws power from the Grey rather than life energy? A possible way to separate necromancy while keeping with the themes of magic harming the environment when used irresponsibly is that necromancy weakens the barrier between our world and the Grey, causing regions to become haunted. Though that may be a topic for another thread.