The game has also been adjusted for improved balance. The game speed was increased, characters were given extra moves and some special attacks were allowed to be used in the air. This was Capcom's response to the several bootleg versions of Champion Edition which were getting spread around the world. In 1992, Capcom released Street Fighter II' Hyper Fighting, or Street Fighter II Turbo in Japan. Also, reversal special attacks were fixed and many moves were adjusted for improved balance. First of all, the four bosses were made playable, which turned the game into another huge success.
Street Fighter II': Champion Edition was released in 1991 and had a number of improvements. This was extremely difficult due to the opponent being able to mix up by doing jabs, twice, once, or none at all after the jump in, and throws being a 50/50 chance of success when both players throw on the same frame. This made safe jumps into tick throws exceedingly strong, as the only chance to escape was via reversal throw. Reversal specials were impossible, with a perfectly timed input resulting in a normal move on the reversal frame (or nothing if performed by negative edge). While being considered the best arcade game by then, it did have a few glitches, and players could not select the same character at the same time. Street Fighter II presented eight selectable characters - a high number by that time - that people could use not only against the CPU, but to face other human opponents. People were used to competing against the CPU for high scores, and most two-player games were cooperative, such as Double Dragon or Final Fight. Street Fighter II: The World Warrior was released in 1991 by Capcom for the CPS-1 arcade board and completely revolutionized gaming. The previous versions were Street Fighter II: The World Warrior Street Fighter II': Champion Edition Street Fighter II': Hyper Fighting ("Turbo" in Japan) and Super Street Fighter II: The New Challengers.
Super Street Fighter II Turbo, or Super Street Fighter II X: Grand Master Challenge in Japan, is the fifth revision of Street Fighter II.