Havoc's Call, Blade of Lordaeron Kings (heroic)

Source
This item drops from the Lich King in the heroic 25-man version of Icecrown Citadel.

Almost all weapons dropped by the Lich King make reference to Arthas Menethil in his path of destruction before becoming the Lich King.

This axe makes reference to Arthas' royal lineage itself, being the future King of Lordaeron, the weapon got passed on to him.