In the game, Sonic has to prevent Doctor Robotnik from collecting six of the Chaos Emeralds in an attempt to rule South Island. He must traverse six "zones", each comprised of three stages or "acts", until he confronts Robotnik for the last time in the Final Zone.

    The gameplay centers around elements that exploit the increased performance of the 16-bit console over its 8-bit forebears. It is notable for being both simplistic and engaging for players.

    At the time of its release, Sonic the Hedgehog was one of the fastest platformers that had yet been released. Sonic could run, jump and roll at significantly higher speeds than most platformers of the time. Unlike other platformers, the game's levels were designed to encourage the player to progress quickly. Springs, slopes, high falls and loop-de-loops were all available to both boost and challenge the player to reach high speeds. This was all accomplished without any slowdown in framerates, adding to the experience.

 

    Essential to the gameplay are the golden rings the player collects along their way in each level; a feature which would become one of the defining characteristics of the series. These items are regularly placed around the level map and serve multiple functions. First, the player collects rings to protect themself. As long as they have at least one ring to their name, the player will not lose a life when injured. Instead, when hit, all rings the player has collected will fly outward and scatter around the immediate area, some of which can then be retrieved before they disappear. If the player runs into an enemy without a single ring, they will lose a life. If the player collects 100 rings they will gain a life, and gain an additional life for every 100 rings after that, provided the rings are not lost.

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