GM Blog : Coming Soon: "The Battle of Crimsonwood Keep"

Already there. It's called Ridley.

What if there's another Ridley Statue inside? =O Seems doubtful actually.

Epic. Definitely. I'm saying, 8 bosses. Grandmasters + Clan leaders sounds about right.

And you don't need to finish all Masteria quests, do you? The only one I can see that you need to finish is getting the Crimsonwood Keystone.

I think you should try to finish all of the Masteria quests just in case. Since Jack Barricade is apparently going to play a crucial role, you'd better finish up his quests. And maybe the Raven Ninja Clan has a part to play too!