Amphibious. The vodanoy can breathe air and water. 

Innate Spellcasting. The vodanoy's spellcasting ability is Wisdom (save DC 14). The vodanoy can innately cast the following spells, requiring only the verbal components: 

At will: druidcraft, shape water
3/day each: misty step, tidal wave
1/day each: black tentacles, watery sphere

Confusing Gaze. When a creature starts its turn within 30 feet of the vodanoy and is able to see the vodanoy’s eyes, the vodanoy can magically force it to make a DC 15 Charisma saving throw, unless the vodanoy is incapacitated.

On a failed saving throw, the creature can’t take reactions until the start of its next turn and rolls a d8 to determine what it does during that turn. On a 1 to 4, the creature does nothing. On a 5 or 6, the creature takes no action but uses all its movement to move in a random direction. On a 7 or 8, the creature makes one melee attack against a random creature, or it does nothing if no creature is within reach.

Unless surprised, a creature can avert its eyes to avoid the saving throw at the start of its turn. If the creature does so, it can’t see the vodanoy until the start of its next turn, when it can avert its eyes again. If the creature looks at the vodanoy in the meantime, it must immediately make the save.

Multiattack. The vodanoy makes three attacks: two with its claws and one with its mandibles.

Claw. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 9 (1d8 + 5) slashing damage.

Mandibles. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 14 (2d8 + 5) slashing damage.