In one Teen Titans episode, Starfire's sister, Blackfire, is comically shown throwing Robin while teaching him some techniques from a strange alien fighting system. The only alien martial art very heavily mentioned in DC are the Kryptonian fighting arts, which are comparable to Yang style combat Tai Chi and Kundalini Yoga. This lead me to wonder....
Is there any canon record or example of DC heroes, in particular Batman, learning any type of extraterrestrial fighting system in-depth?