Lil' Ragnaros, the Tiniest Firelord
Ragnaros, the dread master of all fire elementals, will return in Cataclysm to avenge his defeat in Molten Core. And what better way to head into battle than with a miniature version of the firelord himself following at your beck and call? Lil' Ragnaros, just like his full-scale namesake, burns with constant fury (not to mention flames that serve as a handy cooking fire) and comes equipped with the legendary hammer Sulfuras. And as a being of pure elemental fire,
he has no need to walk from place to place -- he just submerges into the magma below the world's surface when you start walking and reemerges when you stop.