Skull of Gul'dan (Warcraft III)

The Skull of Gul'dan appears in A Destiny of Flame and Sorrow. Unlike other items, it appears as a building that can be targeted and destroyed in order for Illidan Stormrage to consume it.

Its 3D model was originally intended for a building called the "Altar of Chaos", which could have been the Altar of the planned Burning Legion faction.

Ground description: This is the Skull of Gul'dan.

Inventory description: Once a powerful user of Demonic magics, the Demons answered his calls, and found a greater use for his head.

Rather than an oversized skull, the building may have represented the skull and its altar. The Cataclysm quest The Skull of Gul'dan (quest) implies that a red crystal was used as an altar for the Skull of Gul'dan.