Leak or Hoax? Hearthstone: Whispers of the Old Gods
It’s unknown at the moment if this is an early leak or a good photoshop. We’ll have to wait until tomorrow Friday when Blizzard Entertainment announces whatever it is they will announce during the Hearthstone Winter Championship livestream at 1pm EST / 10am PST.
Update# 2: In-Game Shop selling Whispers of the Old Gods
Additionally, this short video showing the in-game store has the Whispers of the Old Gods sale page.
Update # 3: Russian Site: Whispers of Old Gods Photo
Found this russian forum discussing rumors.