"XZ" - figure from the Smash!World "bible"

The XZ are a race of interplanetary Xeno-zoologists. That is, they collect alien life forms (such as Earthlings) and trade 'em with their friends. They visit Earth from time to time to capture wild animals (dinosaurs, elephants, housepets, wayward children and union organizers) for their experiments, or to put on display in cosmic petting zoos.