Violet Bat Paper Charm

Very Rare Wondrous Item
Single use

Paper Ward. While wearing this charm on your person, you are protected by its magic. The first time you fail a saving throw against a spell or magical effect, the magic of the charm is activated. When you do, you can reroll the the saving throw. You must use the new result, even if it is a 1. After the paper charm has been activated, it destroys itself in a flash of harmless pink fire.

Variant of
Paper Charms