While the secrets of time travel still elude our understanding, reality hasnt stopped this tantalizing concept from appearing in dozens of video games. First person shooters, role playing epics, puzzle platformers, and arcade racers have used time manipulation to fuel creative gameplay mechanics from simple do overs to complex historical changes. In Zeit Squared (written with a superscript 2), the ability to rewind time briefly is just one of the various mechanics that make this shoot em up uniquely challenging.