The Lord of the Rings Online Lorebook has been updated with a look at the Gaunt-Lords, Angmar's answer to the Istari.

In the First Age, Morgoth summoned many fell spirits into his service and twisted countless creatures to his will. Among those were dire creatures called Gaunt-men. Morgoth gave the Gaunt-men mortal bodies in which to work his wickedness throughout Middle-earth. Men and Elves alike feared these creatures, for they had the power to instill other fell spirits into the remains of the dead and raise them as wights.

After Morgoth's fall, the remaining Gaunt-men went into hiding in the realm that later became Angmar. Their power was greatly diminished, but when the Wizards arrived to lend wisdom to the Free Peoples of Middle-earth, the Witch-king summoned the Gaunt-men to his service. Among them, five gained greater power to match the five Wizards. These five, embodying death, pestilence, famine, war, and purest evil, became known as the Gaunt-lords.
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