World of Warcraft: Wrath of the Lich King is an expansion pack for World of Warcraft. World of Warcraft: Wrath of the Lich King sends players to the cold, forbidding continent of Northrend, where the fearsome Lich King Arthas Menethil, last seen in Warcraft III: The Frozen Throne, works from his secluded citadel to bring all of Azeroth under his twisted dominion. Players will battle the Lich King's undead army from the shores of Howling Fjord and Borean Tundra to the seat of his unholy power in Icecrown Glacier. In addition, players will be able to advance characters to level 80 and gain powerful new abilities while exploring several new zones and dungeons. The expansion also introduces a number of exciting new features, including an achievement system, expanded player-vs.-player combat options such as siege weapons and destructible buildings, and the game's first Hero class-the necromantic death knight.