Summon forth your Cerberus mount. Be warned, however, that riding into a peaceful village on the back of a gigantic, slavering, three-headed hellhound may cause quite a stir among the locals.
In addition to its immense strength and three gaping maws lined with razor-sharp fangs, this voidsent boasts incredible longevity, having lived since the Third Astral Era. The collars, of Allagan design, are believed to make it as tame as a puppy, though it may simply be biding its time before devouring its keeper.
How to obtain:
Achievement -- Savage Queen of Swords I