Its in the Legendary Invites forum, so obviously you'll need to rank up to Legendary Gamer if not already. EDIT: The thread also states you need to be a Master

Its in the Legendary Invites forum, so obviously you'll need to rank up to Legendary Gamer if not already. EDIT: The thread also states you need to be a Master Gamer, and an account older than 1 year. So very tough requirements, although you can get to MG without uploading anything.