Wondrous item, very rare
This gauntlet appears to be crafted of dark blue scales, with steel spikes made to look like spiral shells and having the smell of seawater.
This wearer of this gauntlet deals 1d8 damage with unarmed strikes. If the wearer already has an enhanced unarmed strike, in which case it grants 1d4 additional damage. Additionally, you can use an action to strike the ground with your gauntleted fist. This will cause a small earthquake in a 60-ft. radius centered on you. All creatures in the area, except you, must make a Constitution saving throw or be knocked prone.
Gods and Icons, Copyright 2016, Dread Unicorn Games; Authors: John WS Marvin, Vanessa Rose Phin, Connor W. Marvin.