The big draw? Unlocked Flood faction.
There's a catch though: This is an FFA with locked teams for everyone except the Flood players. Working together to survive the onslaught without destroying one another will take some coordination and skill. If you're up for the challenge, the journey ahead will be grueling.
If this is primarily playtesters who join up, we'll make one person the Forerunners too. Just for the hell of it.