How Street Fighter II's Computer Opponents Cheat To Kick Your Ass

Illustration for article titled How Street Fighter II's Computer Opponents Cheat To Kick Your Ass
Screenshot: Desk

Have you ever plopped a quarter in the Street Fighter II machine at your local pizza joint and readied up with your favorite character, only to find yourself bashed and bloodied by the CPU just a few rounds later? Perhaps you said something to yourself about the computer cheating, only to get heckled by your friends. Well, according to this YouTube video, it totally was.


Combo expert Desk recently took a rest from breaking fighting games to highlight the ways in which CPU characters cheat in the various arcade incarnations of Street Fighter II. These underhanded tactics include becoming completely invincible for short periods of time, which allows them to interrupt attacks that are normally safe. Desk demonstrates this with side-by-side footage of the same situation being played against the CPU and a human to show just how devious the arcade mode opponents can be.

Let’s say you manage to hit the CPU with enough attacks to stun it. Time for free damage, right? Wrong. Street Fighter II allows CPU opponents to escape the dizzy state in just 12 frames, or 1/5 of a second at 60 frames per second. This is incredibly fast and, to the best of my knowledge, it’s a speed that’s impossible for a human to pull off even with optimal execution. In effect, it’s a little like the rubber-banding tactics seen on the part of AI opponents in games like Mario Kart.

The last bit of Desk’s video covers how the CPU can perform charge and mashing moves—like Guile’s Flash Kick and Chun-Li’s Lightning Legs, respectively—without the requisite inputs. This means Guile can simply walk forward and Flash Kick whenever he wants, forgoing the down charge necessary to pull off the move as a human. Sometimes, the CPU even fakes like it’s charging to give the impression that it’s totally above board.

Much of the info cited in this video comes courtesy of blogger sf2platinum, who has spent years digging through the Street Fighter II code. One post in particular details the AI engine, explaining the game’s unsophisticated methods of turning the CPU into a decent sparring opponent. Give that a look in between frustrating rounds of getting screwed out of your quarters.

Staff Writer, Kotaku


Implied Kappa

Yeah, the charge moves were always the biggest tell. I can grudgingly accept that the AI can pull off four perfect inputs in four frames, but Guile pulling a flash kick out of a forward walk or Blanka launching directly into a roll from a forward walk was always clear evidence that they weren’t playing by the same rules we were.

Between the obviously cheating AI and the level of mastery even the most casual of arcade players have by the time I stumble across a 2-year-old fighting game cabinet, I’ve just never found a good entry point to the genre. Not that there’s any shortage of other games to compete for my time and money, but any time I watch a good tournament match-up with all the suspenseful back-and-forth, there’s a little part of me that wants the feeling of being better than mediocre at at least one fighting game.