I'm currently making a project where any small time or aspiring developers can make a few missions using Unreal Editor 3 inside a universe which I will create shortly.
Each series of missions will be separate from each other, unless you want to collaborate with another developer, but they'll all be in the same universe.
You can create whatever you'd like for you series of missions, but please remain with in plausible grounds (no planets made of cheese). It also has to be compatible with the mainframe, which will require a full UDX.
You can create your own race, but you'll need to make a base character model template for it.
All the power is at your hands - but please, don't troll. I'll just delete anything that is half-assed or doesn't meet my quality standards.
If you still don't get it - it's like a collaboration of missions from developers.
If you're not a developer, but still want to participate, I am also looking for writers and people who are good at coming up with fictional history and cultures.