Octopus
CR 0 · Small Beast · SRD 5.2.1 p. 357
Small Beast, Unaligned
AC 12·Initiative +2 (12)
HP 3 (1d6)
Speed 5 ft., Swim 30 ft.
Skills Perception +2, Stealth +6
Senses Darkvision 30 ft.; Passive Perception 12
Languages None
CR 0 (XP 10; PB +2)
Traits
Compression. The octopus can move through a space as narrow as 1 inch without expending extra movement to do so.
Water Breathing. The octopus can breathe only underwater.
Actions
Tentacles. Melee Attack Roll: +4, reach 5 ft. Hit: 1 Bludgeoning damage.
Reactions
Ink Cloud (1/Day). Trigger: A creature ends its turn within 5 feet of the octopus while underwater. Response: The octopus releases ink that fills a 5-foot Cube centered on itself, and the octopus moves up to its Swim Speed. The Cube is Heavily Obscured for 1 minute or until a strong current or similar effect disperses the ink.