Shield of the Uven Rune

From Waterdeep: Dungeon of the Mad Mage, page 299.

Description
''Armor (shield), very rare (requires attunement). 6 lbs.''

This shield is made from the scale of an ancient white dragon. It has a rune burned into its outward-facing side. A character who examines the rune and succeeds on a DC 20 Intelligence (History) check recognizes it as an uven ("enemy" in Giant) rune that confers great power.

While holding the shield, you benefit from the following properties.

Winter's Friend. You are immune to cold damage.

Deadly Rebuke. Immediately after a creature hits you with a melee attack, you can use your reaction to deal 3d6 necrotic damage to that creature.

Bane. You can cast the Bane spell from the shield (save DC 17). The spell does not require concentration and lasts for 1 minute. Once you cast the spell from the shield, you can't do so again until you finish a short or long rest.

Gift of Vengeance. You can transfer the shield's magic to a nonmagical weapon by tracing the uven rune on the weapon with one finger. The transfer takes 8 hours of work that requires the two items to be within 5 feet of each other. At the end, the shield is destroyed, and the rune is etched or burned into the chosen weapon. This weapon becomes a rare magic item that requires attunement. It has the properties of a +1 weapon. The bonus increases to +3 when the weapon is used against one of the following creature types, chosen by you at the time of the magic weapon's creation: aberrations, celestials, constructs, dragons, elementals, fey, fiends, giants, or undead.