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Outer Spawn: The Third Stage

The Third Stage: Outer Spawn CR 17

This mass of flesh the size of an elephant has numerous tentacles, insect-like legs, and a sucking proboscis intermixed with humanoid eyes, mouths, and noses stretched across its upper body.

XP 102,400
CE Huge aberration
Init +9; Senses blindsight 30 ft., darkvision 60 ft.; Perception +31


AC 32, touch 14, flat-footed 26 (+5 Dex, +1 dodge, +18 natural, –2 size)
hp 270 (20d8+180); regenerate 15 (see below)
Fort +16, Ref +13, Will +20
Defensive Abilities amorphous; DR 20/—; Immune disease, fire, mind-affecting effects, poison; Resist acid 30, cold 30, electricity 30; SR 28
Weaknesses susceptible to dimensional lock


Speed 50 ft., climb 50 ft.
Melee bite +24 (1d8+10 plus grab), 4 slams +24 (1d4+10/19–20), 2 claws +23 (2d6+10)
Space 15 ft.; Reach 15 ft.
Special Attacks feed, trample (4d6+15, DC 30)
Spell-Like Abilities (CL 16th; concentration +21)

Constantgreater invisibility
At willbestow curse (DC 19), confusion (DC 19), death knell (DC 17), dread curse (DC 20), fear (DC 19), greater dispel magic, greater teleport (self only), hold person (DC 17), summon monster III
3/dayblack tentacles, feeblemind (DC 20), fly, phantasmal killer (DC 19), summon monster V
1/dayheal, greater shout (DC 23), insanity (DC 22), power word blind, power word stun, summon monster VIII


Str 30, Dex 21, Con 26, Int 19, Wis 26, Cha 21
Base Atk +15; CMB +27; CMD 43
Feats Combat Casting, Critical Focus, Dodge, Great FortitudeB, Improved Critical (slams), Improved Initiative, Lightning Reflexes, Power Attack, Staggering Critical, ToughnessB, Weapon Focus (slams), Weapon Focus (bite)
Skills Climb +41, Fly +24, Intimidate +28, Knowledge (any one) +27, Perception +31, Sense Motive +28, Stealth +20, Swim +33
Languages Aklo, Common
SQ apotheosis


Apotheosis (Su)

When an outer spawn reaches 100 growth points, it undergoes apotheosis. If this occurs during a proper ritual performed by a cult or spellcaster that focuses the energies, the outer spawn transforms into a unique and powerful avatar of its parent Outer God. Such creatures are equal in power to a Great Old One and are unique and varied in their abilities. If an outer spawn achieves apotheosis when not under the effects of this eldritch ritual, it instead splits apart into dozens (1d20+40) of human-sized outer mutants equal in shape and power to the mutant the original began its life as.

Dread Curse (Sp)

Three times per day, an outer spawn can call down the dread curse, causing coils of rippling, foaming magic to descend from above to strike foes. This spell-like ability functions as unholy blight, but it affects creatures of any alignment and treats them all as good outsiders for the purpose of the spell effect. The dread curse inflicts 10d6 points of damage to all creatures in the area of effect and causes them to be permanently sickened. A successful DC 20 Will save halves the damage and reduces the duration of the sickened effect to 1d4 rounds. This is a curse effect, and the spell-like ability functions as a 5th-level spell.

Feed (Ex)

An outer spawn drains blood and spiritual essence via its bite. At the end of its turn, if it is grappling a foe, it inflicts 1d6 points of Constitution damage (via the draining of blood from the victim) and 1d6 points of Wisdom damage (via siphoning spiritual energy and damaging the victim’s sanity). Whenever an outer spawn kills a creature with its feed attack, it absorbs enough nutrients and soul energy to gain a growth point. Once an outer spawn earns 100 growth points, it undergoes apotheosis (see above). An outer spawn loses 1 growth point per day, so if it doesn’t constantly feed, it will never reach apotheosis. A creature killed in this way cannot be brought back to life via raise dead, but more powerful effects like resurrection still work normally.

Vulnerable to Dimensional Lock (Ex)

When an outer spawn is prevented from using teleportation effects, such as when within an area of forbiddance or under the effects of dimensional lock, its damage reduction and energy resistances are halved and its regeneration is suppressed.


Environment any
Organization solitary, pair, or doom (3–6)
Treasure standard

Yog-Sothoth and other Outer Gods such as Shub-Niggurath and Nyarlathotep are able to produce hybrids that vary greatly in power and size. The outer spawn are typically the most powerful such entities encountered in the normal planes of reality.

The outer spawn is close to its ultimate form, and the traces of its former humanity are few and far between. Often it still has a face or parts of a face, spread across parts of its upper body. Its limbs have become insectoid or tentacular, rather than human arms or legs. It typically resembles a centipede, octopus, or spider creature with traces of the human form threaded through. Outer spawn are huge, reaching the size of an elephant or dinosaur and weighing 10 tons or more.

This is the penultimate “third level” of outer/human hybridization, which has neared the ultimate goal of bringing its parent Outer God to the world physically. An outer spawn is enormous—elephantine in size—and typically always invisible. Like a mutant or abomination, an outer spawn also drains blood and soul energy, but an abomination may need more. The ravenous nature of the outer spawn is alien and terrifying: it can often eat more food at a sitting than its entire body mass, and only its interdimensional nature can explain such a paradox. As its hunger can consume entire herds of cattle or dozens of victims per week, when a cult is trying to maintain its “pet” outer spawn, its activities become increasingly hard to conceal.

Worse, when the cult cannot continue feeding its spawn (as they often fail to do), the monster eventually breaks out of containment and rampages across the countryside.

The Purpose of an Outer Spawn

The ultimate fate of a spawn inevitably takes one of two forms, assuming it is not destroyed by intrepid adventurers or an army sent by the local authorities.

First, the cult or wizard which fostered the spawn wants it to mature and reach apotheosis, that it might bring an avatar of its parent Outer God bodily into the world. This process takes time, energy, and a huge amount of food, and the proper rituals must be performed. Secondly, if these rituals are not performed—if the spawn is alone when it reaches its apotheosis, for instance—instead of becoming the Outer God, it splits into a host of outer mutants, equal in total mass to itself.

Thus, a 6-ton spawn might become 50 or 60 human-sized mutants, which provide the core of a new cult—or a small army to conquer one. Sometimes, these newly born mutants manifest in various places around the world, infiltrating a number of cities or kingdoms.

In this way, the cycle begins anew.

Theoretically, each mutant can go on to become a spawn again given the chance to grow. These mutants typically see each other as siblings or multiple aspects of the Outer God who gave them life. They consider themselves allies in accomplishing the purpose of summoning their Outer God parent, though they can also work against each other as rivals. They compete to determine the one most worthy of accomplishing this purpose, while those proven unworthy become food for the chosen mutant.

Section 15: Copyright Notice

Sandy Petersen’s Cthulhu Mythos, © 2017, Petersen Games; Authors: Sandy Petersen, Arthur Petersen, Ian Starcher.