Castellans of Dol Guldur
From Tolkien Gateway
Template:Fanon The origin of the Castellans of Dol Guldur is not known. Sometimes they are said to be the spirits of those who were imprisoned in Sauron's dungeons, or that they were Elves and Men who sought knowledge and wisdom from the Dark Lord and fell under his sway. The castellans were spirits like, though lesser in power than, the Nazgûl: formless and given shape by their cold steel armour. They were the captains of Dol Guldur and served Sauron with fierce loyalty. However, when Sauron returned to Mordor, there was no more room for the castellans, so they stalked among the trees of Mirkwood.