This is the Don Han’Cho HS Legendary Card from the upcoming expansion Mean Streets of Gadgetzan.
It’s a tri-class card and belongs to the Grimy Goons, meaning it’s playable by Hunter, Paladin, and Warrior.
The text reads: Battlecry: Give a random minion in your hand +5/+5.
You can get Don Han’Cho by opening packs from the Mean Streets of Gadgetzan set.