Tiny aberration, lawful evil

Armor Class 13 (natural armor)
Hit Points 110 (17d4+68)
Speed 5 ft., climb 5 ft., swim 60 ft.

15 (+2) 15 (+2) 18 (+4) 12 (+1) 13 (+1) 8 (-1)

Saving Throws Dex +4
Skills Perception +3, Stealth +6
Senses darkvision 60 ft., passive Perception 13
Languages Aklo, Aquan
Challenge 3 (700 XP)

Special Traits

  • Amphibious. The incutilis can breathe air and water.


  • Tentacle. Melee Weapon Attack: +4 to hit, 5 ft. reach, one target. Hit: 24 (4d10 + 2) bludgeoning damage. If the target was a creature, it must make a DC 13 Constitution saving throw or be paralyzed for 1 round.
  • Ghoulmaster. As an action that provokes opportunity attacks, the incutilis can drive its lesser tendrils into any helpless Small or Medium creature adjacent to it and pump the victim full of poison and chemicals. If the incutilis takes any damage during this process, it is interrupted and stunned until the start of its next turn. The victim must make a DC 13 Constitution saving throw or is killed instantly and becomes a ghoul-like creature under the incutilis’s control, using the stats for a ghoul. This ghoul isn’t treated as being undead and is immune to spells and effects that affect only undead. The incutilis is attached to this ghoul-typically by the head-occupying the same square and moving along with it. The incutilis can make attacks with its tentacles independently of the ghoul’s own attacks. It can also retract its tendrils as a bonus action but doing so causes the ghoul to collapse and revert to a normal corpse. The incutilis must retract its tendrils before it can move away from a ghoul it’s attached to. Any attack that deals damage to the ghoul also deals 1 point of damage to the incutilis, regardless of how much damage is dealt to the ghoul. A character can attempt to attack just the incutilis in this state but has disadvantage on the attack roll. Killing the incutilis destroys the ghoul.


Scholars know life began in the sea, and some- either paranoid or visionary-claim that the sea has manipulated the course of humanoid life through ages beyond reckoning, citing the incutilis as evidence of this. A strange sort of sea creature that appears to be little more than an over-sized cephalopod, an incutilis hides a significant intelligence behind its unassuming appearance. Though most incutilises live their entire lives amid the deepest trenches of the darkest seas, some venture to the border between water and land, revealing terrible control over land-dwelling flesh and an alien disregard for sentient life. Limited in their ability to cross this border and travel on land by their aquatic physiologies, these aberrations overcome this hurdle with a lethal solution, slaying land dwellers and commandeering their flesh to bear the incutilis on shore. To what ends these beings seek to explore the surface remains a mystery-perhaps they do so out of hunger, perhaps out of curiosity, or perhaps because they were sent. A typical incutilis weighs approximately 25 pounds, 30 with its shell, and measures 4 feet from the tips of its longest tentacles to the top of its shell.

Intrusive Controllers. Although incutilises can live as bottom feeders, their favorite foods seem to be higher life forms- sharks, whales, and sentient ocean dwellers-and they appear to make little distinction between the living and the dead, sentient or non-sentient, though usually they avoid dangerous predators and large groups of other sentient beings and preferring instead to operate from the shadows.

Incutilises’ most remarkable physical process is their ability to invasively take over dead flesh. So long as a body is relatively intact, the aberration can extend the smaller, more delicate tendrils it typically keeps retracted into its shell. These tendrils are covered with myriad tiny barbs and smaller fibrous filaments it can wind into even the finest internal apertures of a living body with shocking speed and ease. Once the tendrils are in place, the strange chemical laboratory that makes up an incutilis’s internal organs allows it to secrete strange chemicals and toxins directly into the body’s muscles, causing deliberate contractions, releases, and convulsions that give freshly dead bodies the semblance of life, while those longer dead appear undead. This process requires the incutilis to be latched onto its victim, directing its every motion. If it retracts its tendrils, its host body collapses back into a pile of dead flesh.

Section 15: Copyright Notice

Sea Monsters (5E) © 2021, Legendary Games; Authors Michael Ritter, Michael “solomani” Mifsud, Robert J. Grady, Mark Hart, Jeff Ibach, Alex Riggs, Scott D. Young, Jeff Lee, Matt Kimmel, and Jason Nelson.

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