Sonic the Hedgehog (video game)

Sonic the Hedgehog, often times called Sonic 1, is the first video game in the "Sonic the Hedgehog" series. It was made by Sonic Team and published by Sega for the Sega Mega Drive in 1991. It has many sequels and spin-offs. In the same year, Ancient made a 8 bit version the Master System and Game Gear.
Plot.
In order to steal six Chaos Emeralds, Dr. Ivo Robotnik traps the animals from South Island in robots. The player controls Sonic, whose goal is to free the animals and retrieve the emeralds. If the player collects them all, the game will have a good ending. If the player does not succeed, the bad ending will show Robotnik keeping the emeralds for himself.