The set-up: It all started with an April Fool's joke in the April 1992 issue of Electronic Gaming Monthly. It was the greatest April Fool's gag in the history of gaming journalism, and one that's remained in gaming lore since.
The trick: Beat the arcade version of Street Fighter II, using Ryu, without getting touched. Then survive ten rounds against M. Bison, without dealing or taking damage, and letting the time run out every time. After the tenth, Sheng Long--the supposed master who trained Ryu and Ken--would appear to replace M. Bison.
The catch: "You must defeat Sheng Long to stand a chance," read Ryu's victory taunt in early American versions of Street Fighter II. The only problem is that Sheng Long was never a real character--the name was a Chinese mistranslation of "Shoryu," the "Rising Dragon" part of "Shoryuken," or Ryu's famous "Rising Dragon Punch." Ryu's English taunt was later changed to "You must defeat my Dragon Punch to stand a chance."
The tradition: EGM's prank was so well-executed that it attained urban legend status among gamers of the time. "W. A. Stokins," EGM's "tipster," indeed encouraged avid arcade-goers to waste tokens. EGM repeated the prank in 1997 with the release of Street Fighter III and kept the tradition alive.
The twist: Street Fighter developers Capcom were listening. For April Fool's Day 2008, Street Fighter IV project manager Natsumi Shiozawa posted a blog entry teasing the addition of Sheng Long to the game, requiring similarly ridiculous achievements to meet the extra boss.
The end: This week, 1UP cited Japanese gaming mag Weekly Famitsu in reporting that Sheng Long is appearing in Japanese Street Fighter IV arcade machines as a playable character. Shacknews has independently investigated the claim and can confirm that Sheng Long is to be an unlockable character in the arcade version of the game.
The moral: If you've been a hardcore Street Fighter fan for the last sixteen years, be proud. If you've spent the last sixteen years laughing at gullible kids who tell you they know how to unlock Sheng Long, now's your chance to shine. Remember the story and pass it on to future generations, for the biggest joke in your game's long history just became a fantastic piece of the franchise, never to be forgotten.