Rodd's Raincoat (5e Equipment)

Wondrous item, very rare (requires attunement)

Rodd's raincoat is a yellow raincoat that always smells of fish. The smell persists even after washing.

While attuned to the raincoat, you can reroll the damage dice of an attack made with a weapon once per turn. You must use the new roll. Additionally, weapon attacks that you make that deal piercing damage score a critical hit on a roll of 19 or 20.