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.
Adorned with electrum along the shaft and boasting razor-sharp tines crafted from rock-hard coral, this trident bears only a superficial resemblance to those wielded by marines and gladiators. As you grip it, faint visions of the crashing ocean's tide, a subtle briny scent, and a mysterious yearning to return to the vast kingdom of the sea envelop your senses, even if you've never set foot there.