The Shadow of Orcus
Know as the Demon Prince of the Undead. Tales speak of a time when he ravaged the land destroying kingdoms then raising all those he killed to join the ranks of his undead army. His destruction of the mortal realm was stopped by a mortal known as the Raven Queen. During the his battle with the Raven Queen he was pushed back into one of the portals to the old Shadow Continent and since then has never returned.
According to the death angel messenger the Raven Queen trapped Orcus in the Shadow Continent, but now he seeks his return to the mortal realm and ravage the land once again.