My favorite villains in NH have always been the ones that have the greatest potential for RP when encountered. Pretty much all of the Council of the Black Keep, as well as Skylar are on my list of favorite villains because each of them is a lot more complex than just "we're bad guys." Characters like Bjorn and Demia are fun to interact with for me because part of me knows that had things gone differently in the past, we could have been not just allies, but friends. Characters like Aklead(sp?) and Sashi are great because they're dynamic and well-developed, meaning interaction with them is always a unique experience. Skylar was a villain way beyond my capacity to harm in combat or even remotely handle, and as the first major big bad I encountered, I played Caillen as having a paralyzing fear of him. Gary took note of that, and took the time to do things as Skylar to play off of that. Villains like that lead to fun and intense RP before, during, and after their arrival, and I love every second of it.