Sure. Basically, the Time Eater (from Generations) wants to get revenge on Sonic's world for stealing it from it's home and causing it so much pain. So, with it's powers, it tries to destroy all time, to make the universe it's new home. But before it could complete it's goal, Time Stones stop it from destroying time fully. Now there's only some people who remain - who were protected by the Time stones. They must gather all the time stones and use them to fix time.
However, Time Eater won't give up that easily. Using some of the people it had already erased from time (Basically, all the people on Sonic's world that were 'erased' are like how Sonic's friends were before you completed a level), it sent them out to try and steal the Time Stones away.
^ That's a very short summery of the plot
How it would work is that there would be two 'teams' per-say. Those on Sonic's side who are trying to fix time, and those on the Time Eater's side who are trying to steal the Time Stones. Everyone will submit an app just describing their character (and, there will be some official characters you can be too: Sonic, Tails, Classic Tails, and Silver (Silver is more optional, the others are kinda needed)). After I have a good amount of OCs, and the needed Cannon spots are filled, I will randomly select some of the OCs to be on the Time Eater's side. There can be NO OOC discussion about who's on what side (Only those on the Time Eater's side will know who their team-mates are).
The point is for the characters to discuss amongst themselves who they believe is the Time Eater's spy(All the characters will be 'working together'). Once there characters start collecting the Time Stones, each day one of those who are siding will the Time Eater will steal a stone. The characters will then all have to choose someone who they believe is the culprit... if they guess wrong, the Time Eater gets the Stone. If they're correct, that character is freed from the Time Eater's control.