In the age of battle royale and ever-expanding "games as a service" multiplayer, your "rival" is probably whoever just took you out in the final seconds of a match, ensuring you clinch defeat from the jaws of victory.
Look back across gaming history though, and there are scores of iconic characters knocking seven shades out of each other, for all sorts of reasons. Mythological entities doing battle across time and space, immortal undead ninja-warriors avenging their fallen clans - maybe just two lovely anime chaps with oversized swords fighting on rooftops because the world is falling apart.
Whatever the occasion, the idea of high-profile rivalries spanning multiple generations is something largely resigned to video games, comics or wrestling.
Very few entertainment mediums highlight the sheer fun that can be had from opposing one-upmanship, and with you behind the controls, that's precisely why the following combatants went down in history.