[dizzle98]

Well if you can't stop them from playing there really isn't a lot you CAN do. I mean you can't penalize people for simply not playing big pots with each other. Since you didn't mention any actual collusion like talking during hands and such there isn't much. The big answer obviously would be to not allow them to play if that was an option.

What do you want to do? Force them to all go all-in against one another? Why can't you just not let them enter?