armour of the D. is comprised of several peices of artifact you need to clear up on your hero, because it locks (uses) many parts of the hero's possible artifact.
for example,
Armor of the Damned
Artifacts Needed
Skull Helmet
Blackshard of the Dead Knight
Rib Cage
Shield of the Yawning Dead
You need to free up these places on your hero to put the armour on. Don't have anything on the head, the right and left hand and the torso.
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