I just googled heroscape and I stumbled across the Heroscape room on this website.
http://boardgames.about.com/od/heroscape/ig/Valhalla/
If you scoll to the bottom you will find some concept art, Some figures that have never been seen before like a half marro and half horse which could be an early version of Me-burq-sa but it might possibly be a new marro hivelord for the upcoming waves. There is also a cool looking version of the concept art of Ne-Gok-Sa with a sword and shield.