Dark-Tribe

The Dark-Tribe (Orc."Burgul-Hai") were one of several orcish tribal confederations in which the Orcs of Mordor had split after the Fall of Barad-dur in the War of the last Alliance.The Burgul-Hai were known to be secretive and hid themselves in the shadows and in dark places, rather than open battle they preferred stealth and treacherous murder. After Saurons return during the years of TA 1980-2002 the remaining Burgul Orcs were reorganised and redistributed into newly founded Tribal coalitions where their masters found them useful as Spies, Scouts and Assassins.

See:
 * Morgûl Stalkers

References:

 * Middle-earth: Shadow