TOS #18: Arena

This episode has a familiar plot: the Enterprise is going to visit some friends, who turn out to all have been slaughtered, and the crew discovers it was a trap. They chase the offending slaughterers for a while, until they run into people who talk like this:



These psychedelic aliens suggest that the Enterprise and the Gorn settle their dispute by 1-on-1 combat between the captains. Both captains are transported to a neutral planet and start battling it out.



Obviously, Captain Kirk wins in the end, but not before ingeneously figuring out how to make a diamond bamboo pipe bomb.