Trident of Fish Command [Трезубец командования рыбами]

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.

Source: D&D System Reference Document 5.1, © Wizards of the Coast LLC, licensed under CC BY 4.0.