Golden Hearthstone Card: Lord Jaraxxus

The Golden Hearthstone Card: Lord Jaraxxus is a toy that, upon use, transforms the player into Lord Jaraxxus for 60 seconds. The player's action bars are replaced by a new one which features five buttons that, when clicked, cause Jaraxxus to gesture and spout one of his iconic lines from his encounter at the Trial of the Crusader.

While all players can see the gestures, the voice clips can only be heard by the user.

Source
This item is a rare drop from Gul'dan in the Nighthold on all difficulty modes, including Raid Finder.

Trivia

 * In the Warlords of Draenor beta, the same item ID was used for Pack of Hearthstone Cards.
 * This item is a reference to Jaraxxus' card from Hearthstone which, when used, destroys the player's hero and replaces them with Jaraxxus.