Mailann was one of many who regain his indepedence when Illidan Stormrage assaulted the Icecrown. He joined forces with Sylvanas Windrunner on her campaign to destroy the dreadguards with the help of Varimathras. After the battle was won and Sylvanas took recidence beneath Lordaeron's main capital Varimathras created a new faction in the Forsaken ranks to use infiltration and get intelligence. The Idea was approaved by Sylvanas and Varimathras gathered the Forsaken's most skillfull soldiers who had some experience from their early life with this proffession. Varimathras called them "The Deathstalkers" and would be his elite bodyguards.