To get a clay look with a papier mache costume, it's all in the way you paint it. I would make a head out of chicken wire with paper strips over it., you can either make a mask or make a 3D head that can be dropped over the wearer(that owuld stay on a player more easily). then paint it to look like clay. For the body, I'd say use fabric crusted with real clay.get just a little clay, dissolve it in a big bucket and soak the fabric in it. it would have really nice colors that way. . Papier mache would be unwieldy and would wear out and get all messed up.