For $17 you get a whole book full of new scenarios, monsters, magic items, and soldiers. Plus, if you join in on the nickstarter before March 1st you'll get some stuff for free. Right now, it's a sprew of barbarians, some metal bits to make a captain type figure, and a new sigilist wizard sculpt. The next goal is a matching apprentice.
Much of this supplement was previously available in electronic PDF form, but now it's all put together with new art and a new section in hard copy. Check out the video, and then go put in your order!