Vanguard
The term Vanguard refers to the spearhead forces of the Shadowlords. During the Summer of 2008, they attacked the towns of Cove, Nujel'M, Serpent's Hold, and Papua as part of the Warriors of Destiny event cycle.
The invasion was led by Vanguard Controllers, and assisted by various Undead creatures, Demonic creatures, Dark Wisps, and various red humanoid NPCs such as Brigands and Pirates.
The Vanguard attacked in a sequence, starting in Cove at Midnight UO time (roughly every 2 hours RL time, 3:30pm, 5:30pm, 7:30pm, 9:30pm, etc., etc.). Their coming was heralded with the sudden onset of darkness.