What? This game is a fan game? You've got to be kidding me! That was my impression. This is the best 2D fan game I have ever played! The game is 100% crystal smooth, with a new Sonic sprite the game is superb. Sonic glides overwater and under it, and the game is so realistic! There's underwater bubble refueling stations just like the old games and blocks to break through with a spin dash, but that's jus the beginning. You can also use vehicles, like submarines and cars and more! This game is AWESOME!