Remnants of Angband in the Third Age

With the Balrog of Moria being around in the Third Age, and Gandalf making the statement about older and fouler things than orcs in the deep places of the world. One could assume that there were some if not many remnants of Morgoth’s creations walking around middle earth. Therefore, I would ask anyone if there are any fanfiction cults of Morgoth that rivaled and challenged Sauron’s power in the Third Age. In the Third Age, Sauron had many rivals, namely all the good guys and those who could possess the ring for themselves—but what about evil? Surely, the Balrog, Saruman, and maybe Alatar were all evil rivals that challenged Sauron in some form for dominance of Middle Earth. I see the Remnants of Angband doing this as well, as they would most likely follow Morgoth and not Sauron.

So does anybody have any ideas? Or am I left on my own? This is the last faction for middle earth that I am willing to create, take note though, they wouldn't be too numerous, but they would be tough in numbers probably analogous to Isengard. Thanks for the feeback and look forward to hearing from you soon.

--Gene