Karpov vs. Kasparov
Chess-masters are often intense, brooding characters, which kind of comes with the game's territory. If you're able to succeed in such a strategically challenging battle of wits, you've probably got all kinds of other weird stuff going on upstairs too. That's what made the insane war between Anatoly Karpov and Garry Kasparov the most epic rivalry in all of chess history. After the young prodigy Kasparov beat the reigning champion Karpov in 1985 at only 22-years-old, it was on like Bishop Kong. The pair were so perfectly matched that they insisted on duking it out in over 180 games and five world championships before Kasparov earned the honor of being the best human player of all time (though he was, famously, beaten by a computer in 1996).