Sonic the Hedgehog Winter Consumer Electronics Show 1991 Demo (lost build of Sega Genesis/Mega Drive video game; 1991)
Sonic the Hedgehog is a 1991 action-platformer game for the Sega Mega Drive (known as the Sega Genesis in North America). It was the premier outing for the character of Sonic the Hedgehog and the group behind his creation, Sonic Team. Though the game only received marginal success in its home country of Japan, almost overnight Sonic became a sensation in the West, solidifying Sega's place in Europe and turning the company into a household name in the United States.
Like most games, prototypes and demos are created throughout development to be shown off to the public. One of the earliest playable demos of Sonic the Hedgehog was shown off at the Winter Consumer Electronics Show in Las Vegas in January 1991. The prototype showcases various differences from the final build and has yet to be leaked or released to the public, thus making it lost.
Leaked Footage from CES
Very little was known about this particular demo build until September 2009, when Sonic Scener drx uncovered 2 short clips of the demo in action at CES, featuring numerous differences, even in the first level of the game, Green Hill Zone. Among other noticeable things are the flowers in the level being purple instead of green, the word "RING" instead of "RINGS" in the HUD, and the brief appearance of an Eggman monitor which went unused in the final game. The monitors seen in this footage seem to be cycling through different power-up icons in the footage available, the first monitor which appears can be seen to change between an Eggman icon and a Sonic icon, and the second monitor cycles through the first and second frames of static, and finally to the Eggman icon just as it disappears off-screen. Each frame seems to be displayed for around half a second before changing to the next in sequence - as the player doesn't break either monitor, it is unknown whether the effect of the monitor was intended to be dependent on which icon was displayed when it was broken, or if the programming for the monitors had yet to be finalized and this was simply a test routine for displaying the various different power-up icons. Eggman monitors were later featured in Sonic 3 and Sonic & Knuckles, though if the prototype versions functioned in the same way as in Sonic 3 and Sonic & Knuckles is unknown.
There are also examples of an earlier Ton-ton enemy that attacks in a similar fashion to the Ganiganis found in the final version of the Green Hill Zone, throwing a projectile on either side as opposed to the single-shot they fire in Scrap Brain Zone. Concept art for this variation of the Ton-ton can be seen within the Japanese Sonic the Hedgehog manual. A form of the debug mode is active in the clips, the numbers in the lower right-hand corner corresponding to debug values. Sonic's position is represented differently by the debug mode in the final game.
A higher-quality version of this footage, lacking the frame blending present in the original, later surfaced in March 2012 thanks to YouTube user losttetristgm. The footage was slowed down to allow for closer analysis.