After the defeat of the demon armies and the fall of Archimonde at the Battle of Mount Hyjal, evils have risen from the aftermath. Illidain Stormrage has called forth a mysterious race of sea warriors and begins to travel the world leaving destruction in his wake, while his former enslaver, the elven warden Maiev Shadowsong, hunts him down. Meanwhile, another demon lord from the depths of Hell, Kel'jaden, arises and commissions the three remaining dreadlords (as well as Illidain) to destroy the Lich King, whom has elected to free himself from the control of the demons. Grand Marshall Garishos has formed a post-apocalyptic alliance in order to rebuild what is left of the former great cities, but the Alliance grows corrupt over time. The survivors of the high elves of Quel'Thalas, now known as the Blood Elves, betray the corrupt Alliance and join Illidain. Meanwhile, Arthas continues to destroy remnants of the previous alliance and any signs of life. Arthas's personal forces are summoned by the ailing Lich King to travel to the Frozen Throne, the Lich King's prison, and stop Kel'jaden and the demon forces from destroying him.
—Flotis