Grand Anvil Shield

Armor (shield), rare

A creature must have a Strength score of 15 or higher in order to wield this heavy shield. It can also be used as an anvil for the purposes of smithing.

The shield has 3 charges, and it regains 1d3 expended charges daily at dawn. While holding the shield, you can use your reaction to speak its command phrase ("By the Forge!" in Dwarvish) and expend 1 of its charges when an attacker that you can see within 5 feet of you misses you with a melee attack. When you do, you cause a shower of scalding embers to erupt from the surface of the shield as the weapon grazes against it, dealing 1d8 fire damage to the attacker. A creature that takes this damage must also make a DC 15 Constitution saving throw if it made the attack with a metal weapon. On a failed save, the creature immediately drops the weapon; a creature takes 2d8 fire damage if it picks up the weapon before the end of the turn.

Your strikes upon my shield only make its iron stronger, and its fire hotter.