A Demon (Q."Rauko"; pl. "Raukar"; S.: "Raug" or "Rog"; pl. "Ryg") was an evil Spirit, generally a Maia who had been corrupted by the Black Enemy, a destructive Spirit of Arda, or their incarnate offspring (Maiarindi).
Tied to a hideous Fana (Q. "Veil"; "Radiant Figure") that manifested the theme or element they originally represented, a Demon could almost never assume a fair-seeming form. Their body, though, was critical to their existence in Middle-earth. However, if an Ainu became accustomed to a form and existence within Arda they could become tied to a distinct shape and their Fána became incarnated as a hröa ("Body").
Although the Demons were of diverse appearance, often even unique forms, most of them had a dark shadowy aura similar to dark mist or "Unlight" (for example the Balrog of Moria).
Demons of Renown
Demons of the Legendarium
Boldog Balcmeg Caradhras Carcharoth Dark Hunter Draugluin Dúrin´s Bane Fankil Gaurin Gorgol the Butcher Gothmog Kuruki Langon Lug Lungorthin Miaulë Morgoth Ogrod Oikeroi Old man willow Orcobal Othrod Sauron Shelob Tevildo Thuringwethil Ulbandi Umuiyan Ungolianth Watcher in the Water
Demons mentioned in secondary works
Airatano Aûr Amarthiel Anahristo Bolvag Caran-Carach Caronuial Carrog Coldagnir Cuce-Cebbar Curugûl Draebor Drul Chaurka Duran Durlach Eägoth Eloeklo Enna San Sarab Eos Erebún Erfaug Faucarach Fercha Gaergoth Gan Gaurhir Gelob Gilthrang Gorothir Gulavhar Gwathnor Gwethil Iaurlóke Ior Jäänainen Karagat Kax Kel Lairathin Lesh-Y Lingering Evil Thing Long Lankin Lugbol Maeguen Maroch Magurgoth Máugarth Meklak Mistress of Pestilence Mithia Monstrosity of diverse Shape Moran Morelen Morfana Morgayamar Moria doom spirit Morloch Morrigan Morthrog Mourfuin Mourmaelgax Muar Muddling Annis Mukarg Muul Baas Naruhel Noose of the Sea Ogslap Príclís Pûgudi Razarac Raukoruth Slyardach Sorthog Storlaga Supreme Bulor Telmorng Thaurlach Thindae Tredeinos Tselakus Udûnion Uhiris Umuiyau Unglob Ûpo Warg-King Wight-Lord Xarbanisan Yazhgar Zaken
- Fallen Fire Spirits (Servants of Aule, Vána, Varda or Tulkas)
- Fallen Earth Spirits
- Fallen Spirits of Air (Servants of Manwe, Varda and Orome)
- Fallen Spirits of water (Servants of Ulmo or Yavanna)
- Boldogs and Ogres
- Demons of Vatra
- Gothrogs or Warrior demons (fallen Maiar of Tulkas', Orome's or Manwe's Folk)
- Fallen shadow-spirits (fallen Maiar of Mandos', Irmo's, Este's, Vaire's or Nienna's peoples)
- Fallen Spirits of Arda
- Demonic Creatures