Moonblade (Nashkel Mines)

The Moonblade is a powerful magical sword. When drawn, the sword egde will erupt in blue flames. It's found in the chest of Mulaphy? and can only wielded by Xan, who is chosen by the sword itself to wield it.

In-game description
"This potent weapon was created by the smiths of ancient Myth Drannor. Moonblades are used in the long process of selecting a ruler for the isle of Evermeet. A Moonblade choses its owner, and in the case of this sword it has chosen the elf Xan. Only Xan can use this blade, anyone else who tries will find themselves unable to lift the sword. This particular Moonblade gives resistance to fire and gives its user a bonus to his armor class."