Pankration was apparently the ancient version of what we now call MMA (mixed martial arts). According to Wikipedia, it was "a combat sport introduced into the Greek Olympic Games in648 BC and founded as a blend of boxing and wrestling.
Here's the illustration from the Wikipedia article:
Two athletes competing in the pankration. Panathenaic amphora, made in Athens in 332–331 BC, during the archonship of Niketes. From Capua