Sonic 4 is the sonic 1 remake with modern graphics. I played the demo and noticed that it left out features that made sonic 3 so great, such as checkpoint bonus stages, giant rings scattered throughout the level to enter a bonus stage to get chaos emeralds, the option to play as tails or knuckles and water/fire/electric sheild. I may have heard that it only had 4 main levels as opposed to the 14 main levels found in sonic 3 & knuckles game.
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