This is Sonic 20th Fan edition! A sonic fan-game created for the celebration of sonic's 20th anniversary and the new sonic generations game coming this fall 2011. Play as Modern and classic sonic and load other fan-games into the sonic 20th video game.
Update: This is version 1 of the game. so act 3 vs boss stages and alternate stage tracks between acts 1 and 2 aren't inputed yet. wait until the next update for the upgrade.