After re-watching return of the King, its very clear that many Mordor orcs survived the random hole in the ground opening. I haven't read the books and I don't know much about the expanded lore, but I know the orcs were bound to Morgoth and not to Sauron. So, what happened to them? I'm not sure how Sauron commanded them, did he use some artifact of Morgoth or did the orcs follow him willingly to secure power? Were there such things as good orcs, or neutral orcs? What about Uruk-ai? In the movies you seem some of them in Mordor so I'm wondering since they're bred from man if there is a chance they could not be completely evil. IE. have a chance to survive in the new world.