Orc: Separate skulls (instead of baked in ones)

Request from Discord (Foo): "The baking in of human skulls to certain stamps limits their versatility if you are using these stamps to represent a non-evil tribal society. I think it'd be best if the human skulls were only on stamps that are specifically about the skulls, e.g. trophies, skull spikes, but preferably not on more general stamps e.g. the chests and thrones."