The Crimson Sigil is the most trusted legion of blood elf troops loyal to Illidan Stormrage, and the most elite blood elf forces outside of the Black Temple (Kael'thas doesn't count, as he's thrown in his lot with the Burning Legion). Their headquarters is Crimson Watch, along the Path of Conquest in Shadowmoon Valley. Their most powerful member is Torloth the Magnificent.

The Crimson Sigil managed to capture Marcus Auralion, the high general of the Sha'tar war effort in Shadowmoon, and hold him within a crystalline prison. Players who slay Val'zareq the Conqueror and take his journal can be pointed out to the crystal prison, where Auralion calls upon them to gather their forces and defeat the Crimson Sigil. Upon their destruction, Illidan challenges the players to come to the Black Temple and confront him.

Several members of the Crimson Sigil seem to be undead or corrupted, having the same texture as Dar'Khan Drathir, and several others are wearing Blood Knights outfits but it is unknown if they were part of the order.

List of Crimson Sigil members