This serpentine creature stretches seemingly to infinity, its powerful coils looping and writhing as far as the eye can see. Luminous slime oozes from its every pore and forms a thick coat around the creature. Its tiny head is little more than a ragged mass of tissue fitted with a puckered orifice lined with gnashing teeth.

Image © Matthew Meyer. See more at yokai.com

Taken from the Creature Codex

Ayakachi are predators of the deep that stretch to truly mammoth proportions—the smallest of them is a full kilometer in length. As befitting a creature of this size, ayakachi prey on other ocean giants such as whales, giant squid, sea serpents and other sea monsters. Many of these clashes take place far beneath the ocean’s surface, but radiate turbulent seas and even tsunami for leagues. Ayakashi typically ignore the comings and goings of humanoids on the water, but may accidentally capsize ships by bumping against them or flooding them with luminous slime.

Ayakachi resemble nothing so much as a colossal hagfish, and sages believe they are relatives of these vile creatures. Like a hagfish, the slime of an ayakachi serves as both defensive and offensive weapon, clogging the gills and encrusting around both prey and anything foolish enough to attack it. Ayakashi are solitary beasts, and are believed to reproduce by ejecting their seed into the water to meet with those of other ayakashi. Due to the rarity of these creatures, such matings must happen very infrequently. Ayakachi are too stupid to gather treasure, but waters in which they swim may be littered with wrecks laden with forgotten riches.

Ayakashi CR 19

XP 204,800

N Colossal magical beast (aquatic)
Init +7; Senses blindsight 300 ft., darkvision 600 ft., keenest scent, Perception +26
Aura luminous slime (15 ft., DC 30)


AC 36, touch 6, flat-footed 32 (-8 size, +3 Dex, +30 natural, +1 dodge)
hp 333 (23d10+207); fast healing 10
Fort +22, Ref +16, Will +12
DR 10/-; SR 30
Immune acid, cold, mind-influencing effects
Defensive Abilities deep-born; Weakness massive


Speed 20 ft., swim 120 ft
Melee bite +29 (4d6+14/19-20 plus chew), 1d4+1 slams +29 (2d8+14 plus grab)
Space 50 ft.; Reach 50 ft.
Special Attacks breath weapon (90 ft. cone, DC 30, 19d6 acid plus luminous slime, once every 1d4 rounds), capsize, constrict (2d8+21 plus entrap), entrap (DC 30, 1d4 minutes, hardness 5, hp 30)


Str 38, Dex 17, Con 28, Int 1, Wis 17, Cha 8
Base Atk +23; CMB +45 (+49 grapple); CMD 59 (cannot be tripped)
Feats Combat Reflexes, Critical Focus, Dodge, Improved Critical (bite), Improved Initiative, Improved Iron Will, Iron Will, Mobility, Power Attack, Spring Attack, Staggering Critical, Stunning Critical
Skills Perception +26. Swim +28
SQ endless coils


Environment any oceans
Organization solitary
Treasure incidental

Special Abilities

  • Chew (Ex) Any creature bitten by a ayakashi must succeed a DC 35 Fortitude save or take 1d4 points of Strength and Constitution drain. The save DC is Strength based.
  • Deep-born (Ex) An ayakashi is immune to damage from water pressure.
  • Endless Coils (Ex) An ayakashi can make a variable number of slam attacks in a round, but can only target a single Medium-sized or smaller creature with a single slam. An ayakashi does not gain the grappled condition when grappling a Huge or smaller creature, and can maintain up to 9 grapples as a swift action.
  • Keenest Scent (Ex) An ayakashi can notice creatures by scent in a 1,800 foot radius underwater and can smell blood in the water at a range of 5 miles.
  • Luminous Slime (Ex) All creatures within 15 feet of an ayakashi must succeed a DC 30 Reflex save or be entangled for 1 minute in the ayakashi’s slime. This slime cannot be scraped away or washed away with water, but strong alcohol dissolves it. Any creature that breathes water through gills must hold its breath while entangled by the slime or it begins to suffocate (creatures that breathe water through magical means are unaffected). An ayakashi is immune to the effects of its own luminous slime and those of other ayakashi. An ayakashi radiates light as a candle, and any creature entangled by its slime does so as well. The save DC is Constitution based.
  • Massive (Ex) Because ayakachi are so massive, uneven ground and other terrain features that form difficult terrain generally pose no significant hindrance to an ayakachi’s movement, though areas of forest or settlements are considered difficult terrain to an ayakachi. A Huge or smaller creature can move through any square occupied by an ayakachi, or vice-versa. An ayakachi can make attacks of opportunity only against foes that are Huge or larger, and can be flanked only by Huge or larger foes. An ayakachi gains a bonus for being on higher ground only if its entire space is on higher ground than that of its target. It’s possible for a Huge or smaller creature to climb an ayakachi—this generally requires a successful DC 30 Climb check, and unlike the normal rules about ayakachi and attacks of opportunity, a Small or larger creature that climbs on an ayakachi’s body provokes an attack of opportunity from the monster.
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