From Wikipedia The game is played from an isometric viewpoint in a 2D environment and uses pre-rendered 3D sprites. Sonic must collect Flickies (first featured in the 1984 Sega arcade game Flicky) by finding and destroying Badniks located around the level, and bring them to a warp ring in order to advance in a zone. Sonic can use the Flickies he has rescued to reach items above springs to earn continues. If Sonic is hit, the Flickies and all of the rings he has collected thus far will scatter and Sonic will have to gather them up again. They will also individually scatter if they are hit separately to Sonic. Each zone consists of two regular acts and one boss act. There are 10 or 15 Flickies in each zone's regular acts, barring Panic Puppet's, while in each zone's third act the player faces Doctor Robotnik (Dr. Eggman in some regions) in one of his many machines.