Vaughn is a weaponsmith in The Amnoon Oasis.
If you give him the required amount of crafting materials, and pay him a fee in gold, he will craft you one of the weapons from his "menu". His +5 energy axe and longbow are notably cheaper than the ones offered by Shichiroji from Divine Path and Ruricu in Crystal Overlook. Also, for a fee of 10 gold he can customize a weapon for you. This will increase its damage by 20%, but means that no character other than the one it is customized for (and his or her heroes) can use that weapon.