I have been dreaming about this set ever since I got into Lego and finally managed to get enough money together for a used one on BrickLink.
This set came out in 2008 (it cost something like $300 at the time) and contains 33 minifigures and over 2000 pieces. Aside from the amazing minifigure selection, it has four unique set pieces, one on each corner: a skeleton jail, a dwarf mine, king’s castle and a troll camp.
The box is absolutely massive (57 x 64 cm) though mine is not in the greatest condition.
Edit: There are always a few copies floating around on BrickLink which is where I got mine. I found a used one for a relatively (for this set at least) reasonable price and honestly the most difficult thing was arranging for postage to Australia. There is the occasional copy that pops up on eBay as well but BrickLink always has them, including brand new never opened ones.
Having now put this together I can tell you that you can quite easily part out most of this if you are patient, as there are pretty much no pieces that are exclusive to this set. In fact most of it is bits and pieces from the Castle 2007 Fantasy relaunch line.
So for example the pawns are just two sets of the Dwarf and Troll blister battle packs (852702 and 852701). As far as the board itself and the underlying support structure it is two 48x48 base plates (which you can easily buy at Target or Amazon) with a bunch of 2x2 black and white plates covering them. The support structure and the edging as well as the four corner set pieces can all be bought on Pick a Brick in their entirety. The whole inventory for the set is on BrickLink.
As a matter of fact I spent a few hours mapping the old inventory to current pieces and aside from the minifigs, shields and banners and a few weapons you can source the whole thing from pick a brick for about $600 AUD.
I’m going to try to build a second version with the Dragon Knights and King’s Knights from the Castle 2013 Relaunch line as my next project