This is the Jade Behemoth HS Druid Card from the upcoming expansion Mean Streets of Gadgetzan.
It’s a Druid class minion and the card text reads: Taunt. Battlecry: Summon a Jade Golem.
You can get Jade Behemoth by opening packs from the Mean Streets of Gadgetzan set.
If you want to find out more about Jade Golems and how this mechanic works check this post.