- "But the Great Eye has seen it. Even now he presses his advantage. His attack will come soon."
- — Saruman, to Gandalf, The Lord of the Rings: The Return of the King
The Red Eye, also known as the Great Eye, the Lidless Eye, the Eye of Sauron or simply the Eye, was the heraldry of Mordor and of Sauron the Dark Lord, as its ruler. It was also used by vassal territories, such as the Orc-occupied Moria and Dol Guldur, as well as Harad.
Appearing on banners and painted on shields and helms or on the heads of Mûmakil, the Red Eye was borne by the main forces of the Dark Lord, such as the army in the service of the Witch-king of Angmar. Orcs also marked the symbol on desecrated statues, as seen in Mirkwood and the borders of Mordor. The emblem usually depicted a red eye on a field of black. Aside for being a mark of allegiance, it stood for Sauron's delusions of grandeur: Sauron desired to be a god-king over the whole Arda and was held to be this by his servants, who hailed their master as the all-seeing and all-knowing Lord of the Rings and of Middle-earth; the Eye was therefore a symbol of the divine omnipotent status that the Dark Lord coveted.