If there is more on Diablos it has to be from somewhere that's not the 2nd Lore book as the 2nd one doesn't mention anything about him being a Wol corrupted by auracite from the 13th. Just that he was used by Machi as a weapon against Amanpour. Along with his Hallowed form just made him stronger to attacks. Don't get me wrong I'd love to know more about the various WoLs who failed to save their shard. Along with hope that we can maybe some day reverse as much darkness as we can for the 13th.