The 4th Party, Since Poser is based heavily on 3rd party models, I suspect that the successive challenges will allow them, but its up to the previous winner. If a winner wants to say Poser Purist, then so be it. If the previous winner says yea or nay to postwork, or limits to portraits, or expands to anything that fits a theme of 'fantasy' then that's the deal. The challenge should be open to all versions of Poser though. I'd recommend that you look at the past and current Bryce challenges to see how I hope this goes.