you then land in chemical plant. they stop chasing you, but you have to get through act 2... then the boss appears, and kills sonic. amy then defeats robotnick, and bad ending. for a good ending, you would need to find the chaos emreals in simalr fashion of sonic 1 SMS. And instead of sonic being dead, he steal the emrealds, defeats robotnick and runs away. then amy gives up. the end.