Electronic Gaming Monthly stated in their 46th (May 1993) issue that the version featured at the show was 75% complete, while the preview copy they received was 80% complete. Just like the character sprites, the differences range from subtle to drastic but overall seems to be based on the same set of data: Even the game’s soundtrack got somewhat reinterpreted in the Turbo ROM. Sonic Boom. Ryu. Through a little bit of disassembly work with the help from IDA Pro, Exodus Emulator, and BizHawk, we were able to pinpoint the main subroutine that's used to decompress and load tiles along with any subsequent palette data. As quickly as it was announced it was dropped in favor of covering the superior Special Champion Edition. So if the game was ready to be released, where was it? It's possible that the Turbo ROM was an internal build never distributed for marketing that somehow leaked and sold as a bootleg. While it seems that it was initially targeting an August release in an attempt to come out at the same time as Hyper Fighting (according to Mean Machines Sega (July 1993) and MEGA UK #9 (June 1993)), the game would eventually hit its other targeted release date of September 27th that year. Due to this revelation, there was renewed interest in researching the origins of the ROM as well as the original Champion Edition. Unlike most bootlegs that disguise their "originality" by hacking preexisting games, this game is completely unique and isn't based on the Special Champion Edition or some other fighting game on the same system. Unlike most bootlegs that would do everything in their power to remove any trademark or copyright information, this build contains a Sega logo upon start up. The only compromises which were reported at the time were the backgrounds that lacked polish, some missing character animation frames, the opening sequence, and a weaker color palette. We can assume that Capcom would've had to rely on a developer with previous experience in Mega Drive development. This is another indicator that the game was very close to being finished before it was cancelled.
The original arcade version of Street Fighter II (known as Street Fighter II: The World Warrior) was released worldwide sometime in March of 1991. And finally, a special six-button controller and arcade controller would be produced specifically because of the port. News/The Lost Street Fighter II: Champion Edition for Sega Mega Drive Thankfully, we recently acquired two prototypes of the original canceled version and we were able to make accurate dumps of each for the sake of preservation. Instead, we must look at something that would've been proprietary to that specific developer. Street Fighter II was possibly one of Nintendo's largest system sellers, which guaranteed a larger pool of potential customers to sell their other software to. These EPROMs were most likely burned for previews/reviews for certain magazines in Europe. The music tracks for things such as the credits sequence are present despite never being used in the game itself. Despite this, many of the magazines that reported the initial rumors of the Mega Drive port cited that legal issues were the primary reason for the game's many, many, many delays. Most of these very early rumors were consistent in detailing three specific things about this port. This all seems to suggest that the dump originated from the Chinese bootleg scene, possibly being dumped from an original pirate cart much like how the The original box art for the Turbo bootleg. Not every mention of Capcom had been erased, however, as references to Capcom are still present in various areas in the game itself.
The exact origins of this version of the game in particular is a mystery, as the game was leaked after the release of the Special Champion Edition. Despite everything mentioned by the media so far, it seemed that things were looking great for Sega! This was because it was discovered that Sonic 2 had been leaked from a magazine based in the UK, and so an order was set in place to prevent further leaks from occurring. Below is the original press announcement that quickly found its way to Usenet at the time: Since some journalists were at the event, a few pictures were taken as well. Mean Machines Sega revealed in their August 1993 issue that the prototype on display only featured two playable characters (Ryu and Ken) and one stage.
For a bootleg, this game is certainly noteworthy in comparison to other original hacks that came from China or Taiwan. Shown above, the beginning of the decompression routines used for compressed art archives in the Turbo ROM. We also couldn't find a single magazine that included screenshots of a version of the Champion Edition without the black bar at the top of the screen. It's likely that the July prototype was used for reviews for the Champion Edition but communication issues between Sega and Capcom prevented builds of the Special Champion Edition from being used instead.
The Capcom has also produced fighting games involving licensed characters from other companies and their own properties. ROMs were often categorized and sold in sets on either floppy disks or CDs in flea markets around the world. The CES build was not allowed to be photographed as it was in such an early state that it was possibly very unrepresentative of the final game. However, the gameplay was faster and more responsive in comparison to the original SNES release. Thankfully, we recently acquired two prototypes of the original canceled version and we were able to make accurate dumps of each for the sake of preservation. The sound driver used in the Special Champion Edition hinders a lot of the sample playback, resulting in a very “thin” sounding game. A ROM hacker could add the code/data that they wanted to change or add to these areas and then alter either the original offset or line of code that refers to the original location to the new "hacked" location. Shown above, the beginning of the decompression routines used for compressed art archives in the Turbo ROM. The game initializes $F300 in RAM with these names, but there are no routines that utilize this data for any purpose. A release date of June 1993 was announced and a cartridge size of 16mbit was announced as well. Performing any form of a hack on a structured blob of code and data limits what you could actually do to a ROM.