Trident of Fish Command
Source: Dungeon Master's Guide
Weapon (trident), uncommon (requires attunement)
This trident is a magic weapon. It has 3 charges. While you carry it, you can use an action and expend 1 charge to cast Dominate Beast (save DC 15) from it on a beast that has an innate swimming speed. The trident regains 1d3 expended charges daily at dawn.