Merrow
Large Monstrosity, chaotic evil
Armor Class 13 (natural armor)
Hit Points 45 (6d10+12)
Speed swim +40, walk +10
Challenge 2
Senses darkvision 60 ft., passive Perception 10
Languages Abyssal, Aquan
Special Abilities
Amphibious. The merrow can breathe air and water.
Actions
Multiattack. The merrow makes two attacks: one with its bite and one with its claws or harpoon.
Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 8 (1d8 + 4) piercing damage.
Claws. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 9 (2d4 + 4) slashing damage.
Harpoon. Melee or Ranged Weapon Attack: +6 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 11 (2d6 + 4) piercing damage. If the target is a Huge or smaller creature, it must succeed on a Strength contest against the merrow or be pulled up to 20 feet toward the merrow.
Source: 5e Core Rules · OGL/Open