Wave Fury (5e Equipment)

Weapon (maul), very rare (requires attunement)

The Wave Fury (sometimes referred to as the Tempest of the Depths) is a weapon granted to the triton people by the goddess Aoea from ages past to mark the coming of a great warrior among their ranks.
You have a +1 bonus to attack and damage rolls made with this magic weapon, which deals an additional 2d6 cold damage on a hit. When you attack a creature with this weapon and roll a 20 on the attack roll, that target takes an extra 2d6 thunder damage and must succeed on a DC 15 Constitution saving throw or be deafened for 1 minute. An affected creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.