well eventually they'll start most likely hunting for each other, and some may just sit and wait, for others to come to them.. though i could start it off where everyone works together and everything... then towards the end after they fight some powerful enemies, then they starting having to do what they must to be #1, which some will void their chance while others would just instantly attack. etc.... depending on the character's personalities.

At the start it's basically them trying to find out what happened to them, why this is going on, and for some if there is another level they can reach. which all leads them to the same ruins.