IDK what i could really roll with, since the durability of his body determines not only how good his defenses are, but also how sturdy his weapons will be. I'm afraid that i choose a material that would make for a satisfactory weapon, it would be too tough as a defense, and if i choose something your characters deal with, it'll make for shit blades, limiting him to just bludgeoning his opponents, or stabbing, and hoping that the tip won't break or blunt too much.