Archmage Arugal is the former final boss of Shadowfang Keep in World of Warcraft.
He was formerly a citizen of Gilneas who became a member of the Kirin Tor, the order of mages based out of Dalaran. However, after the Scourge destroyed Dalaran and most of its populace, he fled to Shadowfang Keep above Pyrewood Village. He was later called on by Genn Greymane, King of Gilneas, to aid Gilneas during the third war. He summoned worgen in order to combat the Scourge. Though the worgen were successful in slaughtering the Scourge, they soon became too feral for Arugal control and rebelled against the magi who controlled them. Arugal was driven insane with guilt and adopted the worgen as his "children", and once again claimed Shadowfang Keep as his own. He fell under the control of Alpha Prime, leader of the worgen, and spread the worgen curse throughout Silverpine Forest, and eventually, to Gilneas. He would later be killed by Horde adventurers after drawing the ire of the Forsaken.
During the events of Wrath of the Lich King, the Lich King sends his servants Prince Valanar, Prince Keleseth, Prince Theraldis, and Prince Atherann to revive Arugal (who was buried at the foot of Shadowfang Keep after his death at the hands of Horde adventurers) as a ghost in service of the Scourge.
He was then sent to the Grizzly Hills in order to turn the human populace into worgen; he is successfull in doing this in the villages of Silverbrook and Solstice Village. In doing this, Arugal managed to form his own Wolfcult, comprising mostly of humans who willing joined (with the alternatives either being killed or condemned to undeath) and the existing worgen of the Bloodmoon pack. However, he is once again killed by adventurers.
By the time of Cataclysm, Lord Vincent Godfrey has taken his place as the Lord (and final boss) of Shadowfang Keep.