The lair of Vulcanus is a unique dungeon that can be accessed at level 30 or higher, but can only be entered alone. To enter, you must collect 20 Tiny Souls and take them to a Shrine of Vulcanus, where you can use them to enter his molten prison. Once inside, you must face waves of Vulcanus's fiery minions, then descend further into the prison with more imprisoned Souls. Only after defeating all of Vulcanus's minions will you face Vulcanus himself. Remember, though, that this is only a shard of his true power, so gather your courage and achieve victory!