I have both versions rigth now, play them sid eby side, teh graphics are exactly the saem, theonly difference is teh backgrounds have more details on SNES characters and such are IDENTICAL. SNES had 2 differences form Genesis, Subzero was a slight green tint in Genesis due to lack of colors and Jonny Cage "green fireball' was silver same reason.
The ONLY levels that BG images were different were the COurtyard and Pit and Goros lair. Courtyard had water falls and mountains on SNES Genesis has sky and clouds. Pit had mountain in BG SNES but was missing form Genesis. Goros lair had all the bones in the correct plaes on SNES where Genesis had just 1 skeloton and some bones were smaller in scale and not as clear to see.
The Jonny Cage fireball was green on SNES and Sub Zero was dark blue like arcades. Genesis versions had all the background music and soudn effects and MOST voices the only voices it was missing were the characters names and FAtatlity and Finish HER, Finsih HIM was said out load but HER was not. The Sega Genesis version had some BG music files remixed to more techno sound than SNES which had more oriental sound.
Genesis version had teh Oroginal FMV seguences form arcade but in stillimages instead of motion, SNES had a green BG with teh characters doing thie finish stance, totaly different. SNES changed the bios and endings to use charcters images form fight select screan,m Genesi had original arcade images.
Also SNES had Reptile but he wasnt programed the same and was harder to get to, Genesis not only ahd Reptile but also teh Green SOny which was NOT in SNES version.
Genesis also had the DULLARD code which allowed many things to be changed, some were cheats others were just fancy options. SNES had NOTHING extra. The only voices it had that Gensesis didnt have weer the characters names at character select and Finish HER and Raidens yekk when he torpedos.
Genesis had ALL the soudn effects except some bone crunching sound and screams for fataloities. SNES was also misisng these same fx and screams as fatalitiew were altered.
Gnesis had the toned down fatailities and teh bloody ones too, which doubled the number of fatalities effectivly adding more content to teh game
BOTH versions ahd different ending form arcade ut Genesis was longer and had more animations than SNES version, which just ahd Shang TSing lsoing his souls and running the credits, GEnesis had Tsung burst into flames and then had each character flip onto and off screan when actors name was called. then goro was displayed and then credits were rolled. Both versions had identical to arcade Specila stages (test your might) and both versions had all the same layout except SNES had options to adjust yoru heath meter and Gensis had Very Easy, Easy, Medium, Hard and very hard and also number of credits, SNES didnt let you adjust credits.
I have over analized EVERY version of these games and if you play teh Genesis version you DO get more content than SNEs version plus you get extras not in teh arcade and you get bsicaly equal graphics.
SNES had some enhanced BG images and tahtw as it. Both versions even had the 2 player battle VS screan which was removed from the Genesis in MK 2.
I will say again I have both versiosn now as did when both were new and GENESIS was the HANDS DOWN better versions, only thing SNES had was a few voices and some Bg images. colors werent that big a dela becaus eonly a hadnfull of colros were even noticably different.