New Idea for a Game

I was inspired to come up with this by SilverPlays97's poll about transformations. What if sometime before the games events, Sonic manages to collect all 7 chaos emeralds. Then early in the game something sparks a transformation into Dark Sonic, he somehow manages to get access to a continuous supply of chaos energy allowing him to sustain the transformation. Then the rest of the game is about the other characters trying to stop him, Making Sonic more like the antagonist instead of the protagonist. What would you think if this happened.