Trident of the Vortex

Weapon (trident), very rare (requires attunement)

This bronze trident has a shaft of inlaid blue pearl. You gain a +2 bonus to attack and damage rolls with this magic weapon.

Whirlpool. While wielding the trident underwater, you can use an action to speak its command word and cause the water around you to whip into a whirlpool for 1 minute. For the duration, each creature that enters or starts its turn in a space within 10 feet of you must succeed on a DC 15 Strength saving throw or be restrained by the whirlpool. The whirlpool moves with you, and creatures restrained by it move with it. A creature within 5 feet of the whirlpool can pull a creature out of it by taking an action to make a DC 15 Strength check and succeeding. A restrained creature can try to escape by taking an action to make a DC 15 Strength check. On a success, the creature escapes and enters a space of its choice within 5 feet of the whirlpool. Once used, this property can’t be used again until the next dawn.