War against the Jailer

The war against the Jailer was a conflict between the Mawsworn led by Zovaal the Jailer and his allies, and the Covenants of the Shadowlands with the help of the Maw Walkers.

After the end of the war against the Lich King, Sylvanas Windrunner hurled herself from Icecrown Citadel in order to commit suicide. Instead, she met with the Jailer, an ancient evil who rules the Maw of the Shadowlands, and started working with him.

When Warchief Vol'jin died during the start of the third invasion of the Burning Legion, he heard whispers from a dark entity which told him to make Sylvanas the new warchief. After the troll's death, Sylvanas said that "in the end, death claims us all" and accepted her new title.

After the end of the demonic invasion, Sylvanas started the Fourth War in order to kill as many people as possible in order to feed their souls to the Maw which allowed Sylvanas and the Jailer to both grow greater in strength.