Become a hero in Azeroth and earn a hero in Hearthstone
All you need to do is level a character to 20 in World of Warcraft, and you’ll earn a new Achievement, Fledgling Hero of Warcraft, that will unlock Liadrin for use in Hearthstone.
No World of Warcraft subscription is necessary to earn this hero and bring the power of the Light to bear in Hearthstone—simply log in to your existing account now and play.
Note that while this Achievement will not be rewarded retroactively, anyone who leveled a character to level 20 after March 11 will be eligible to receive Lady Liadrin.
Once earned, you’ll be able to find your new hero waiting for you in your Hearthstone collection (My Collection) under the Heroes tab.