The combined efforts of the World of Warcraft community have now unlocked a piece of epic in-game music that is part of the encounter with Arthas in Icecrown Citadel: 'Invincible,' an ode to one who has fallen. Time and events have left it unclear whether the song refers to the former prince of Lordaeron or his beloved steed. This unlockable stream will be the first chance to hear the piece in its entirety.

Head over to the World of Warcraft anniversary site and listen to 'Invincible' now! Also, make sure to send in your Battlecry Mosaic pictures for more cool unlockables.