Super Street Fighter II Turbo

Super Street Fighter II Turbo
An update of the game, Super Street Fighter II X - Grand Master Challenge (known as Super Street Fighter II Turbo outside Japan and abbreviated as Super Turbo, ST or SSF2T'), was released in 1994 and featured enhanced speed and difficulty, as well as the first appearance of the then-secret fighter Akuma. It also was the first game in the series to have "super combo" moves. The game was ported to the 3DO in the same year, with an exclusive remixed soundtrack, which has since been added into other compilations of the Street Fighter franchise including the console version of Hyper Street Fighter II. It was later also ported to the PC, the Amiga (AGA only), the Sega Dreamcast as part of Capcom's Matching Service which allowed for head-to-head online combat, the PlayStation and Sega Saturn as part of Street Fighter Collection, and the PlayStation 2 and Xbox as part of Capcom Classics Collection Vol. 2. Another version of SSF2, called Super Street Fighter II X Revival (Super Street Fighter II Turbo Revival outside Japan) was released on the Game Boy Advance in 2001. A new version titled Super Street Fighter II Turbo HD Remix is scheduled for release on the PlayStation Network and Xbox Live Arcade in Fall 2007.
Old Characters
Super Street Fighter II Turbo introduced the concept of inputting a code to play as the old "Super" character if the player did not like the "Turbo" character. The character would play like how they would in Super Street Fighter II, with the option of pressing Jab Punch and Short Kick together for the alternate character color. This method has its strengths and weaknesses. Old characters cannot do the Super Combo moves and they cannot flip out of a throw. On the other hand, some features are considered welcome, such as at the start of a Dragon Punch, Old Ken and Old Ryu are completely invincible and cannot be hit out of it (Turbo Ken and Turbo Ryu can be hit out of it at any point).
Introduction of Akuma
Super Street Fighter II Turbo also saw the introduction of the series' first hidden character, Akuma. Should the player succeed in defeating all preliminary opponents, as well as Balrog, Vega and Sagat without using any continues (or to a greater extent, without losing rounds), he will reveal himself. Once the player reaches M. Bison, at the start of the round Akuma will warp in, and dispose of Bison using the Shun Goku Satsu. There is no name on Akuma's lifebar, the portrait is completely black and different music is playing.