Quote Originally Posted by parvo View Post
I don't know how.
Ask in a trade/advice/general channel and someone'll come along and do it for you. Instantly levels you from 8 to 16, it's a "get into the expansion pack content quickly" button that is available until August 15. As you're starting on barbarian it wouldn't be a bad idea to do it this life but you'll be getting significantly less XP than if you did it on a Legendary life (whatever proportion of 4.3 mil vs 1.9 mil).