Rakanishu

Rakanishu is presumably a fire elemental featured in the Kobolds & Catacombs expansion for Hearthstone. It lives inside King Togwaggle's crown, which was given by Arch-Thief Rafaam.

Trivia

 * Rakanishu was originally one of the Fallen leaders in Diablo II, encountered in Act I of the game.
 * He is also referenced in World of Warcraft, as kobolds in Highmountain will sometimes yell "Rakanishu!" in combat, just like the Fallen monsters did in Diablo II.