Giant Octopus

Large beast, unaligned

Armor Class 11

Hit Points 52 8d10+8

Speed 10ft Swim: 60ft

STR

17 +3

DEX

13 +1

CON

13 +1

INT

4 -3

WIS

10 0

CHA

4 -3

Skills Perception +4 , Stealth +5

Senses darkvision 60 ft., passive Perception 14

Challenge 1 (200 XP)

Hold Breath. While out of water, the octopus can hold its breath for 1 hour.
Underwater Camouflage. The octopus has advantage on Dexterity (Stealth) checks made while underwater.
Water Breathing. The octopus can breathe only underwater.

Actions

Tentacles. Melee Weapon Attack: +5 to hit, reach 15 ft., one target. Hit: 10 2d6+3 bludgeoning damage, and the target is grappled (escape DC 16). Until this grapple ends, the octopus can't use its tentacles on another target.
Ink Cloud (Recharges after a Short or Long Rest). A 20-foot-radius cloud of ink extends all around the octopus if it is underwater. The area is heavily obscured for 1 minute, although a significant current can disperse the ink. After releasing the ink, the octopus can use the Dash action as a bonus action.