Formless Spawn

Formless Spawn CR 8

This black ropy construct of thick organic material swiftly changes form, emitting rope-like tendrils and building legs, mouths, and other structures seemingly without pattern. It is utterly silent despite the chaos of its ever-moving structure, though you keep expecting some sort of noise like a babbling brook or trembling pool of water.

XP 4,800
CE Huge ooze
Init +9; Senses blindsight 120 ft., tremorsense 240 ft.; Perception +11


AC 22, touch 22, flat-footed 13 (+5 deflection, +9 Dex, –2 size)
hp 105 (10d8+60); fast healing 10
Fort +9, Ref +12, Will +4
Defensive Abilities all-around vision; DR 10/—; Immune acid, ooze traits; Resist electricity 10; SR 19


Speed 60 ft., climb 40 ft., swim 60 ft.
Melee bite +15 (4d6+6 plus grab) or 3 club tentacles +15 (2d4+4) or 12 whip tentacles +9 (1d4+2) or ram +14 (6d8+6/x3)
Space 15 ft.; Reach 15 ft.
Special Attacks fast swallow, swallow whole (2d4+4 acid damage, AC 12, 10 hp)


Formless spawn simply re-form after being cut or chopped. They are extremely fast and intelligent, so they can and do flee superior foes clever enough to focus on high-damage magical attacks.

Each combat round, the formless spawn can take a different shape and use a different attack system, as the combat demands. If an enemy is significantly smaller than the Spawn, it can open up a huge toothless mouth and swallow a victim whole.

A formless spawn frequently transforms its whole body into a pointed deadly ram and thrusts at a single, large enemy. Its club attacks are generally reserved for heavily-armored foes. The formless spawn’s whip attacks are lashes with many small tendrils sharpened to razors, which slice lightly-armored enemies to shreds.


Str 19, Dex 29, Con 22, Int 15, Wis 12, Cha 15
Base Atk +7; CMB +13; CMD 37 (cannot be tripped)
Feats Combat Expertise, Combat Reflexes, Power Attack, Weapon Finesse, Weapon Focus (club tentacle), Weapon Focus (bite)
Skills Climb +17, Knowledge (religion) +12, Perception +11, Stealth +11, Swim +17
Languages Aklo
SQ compression, improved swallow whole, freeze, variable attacks, tentacles


Freeze (Ex)

A formless spawn can hold itself so still that it appears to be nothing more than a puddle of tar or oil. When using this ability, a formless spawn can take 20 on its Stealth check to hide in plain sight as just such a puddle. While freezing in this way, a spawn need not drink or eat.

Improved Swallow Whole (Ex)

When a creature cuts its way out of a formless spawn after being swallowed whole, the monster’s fluid body reforms instantly, allowing it to continue to use the swallow whole attack without needing to completely heal all damage.

Tendrils (Ex)

A formless spawn fills an area around it to a twenty-foot radius with a writhing storm of black tendrils formed from its own amorphous body. These tendrils grant it a +5 deflection bonus to AC and penalize all other creatures’ CMB checks made in that area by –5. Freedom of movement grants immunity to this CMB penalty, and creatures that are gaseous or incorporeal do not suffer the penalty.

Tentacles (Ex)

A formless spawn’s club tentacles always function as primary natural weapons that inflict bludgeoning damage. Its whip tentacles always function as secondary natural weapons that inflict slashing damage.

Ram (Ex)

As a full-round action, a formless spawn can transform its whole body into a deadly pointed ram and thrust at a single foe. This primary attack inflicts piercing damage.

Variable Attacks (Ex)

When a formless spawn attacks, it must choose which form of attack it wishes to make in that round between a bite, up to three club-like tentacles, a number of whip-like tentacles, or a single powerful ram.

When it makes attacks of opportunity, it always does so with a club tentacle. It cannot attack with multiple attack types as part of a full-attack action—it must choose one of the four attack modes but is free to change those modes each round of combat.


Environment temperate ruin
Organization solitary or flood (2–6)
Treasure standard

Deep below the earth live the formless spawn of Tsathoggua. They are highly fluid entities of black protoplasm, which can shift between shapes with the rapidity of water. They are liquescent in their native habitats, and build channels or gutters of stone that they can flow through with incredible speed. Their preferred resting-place is a tub or a depression in the earth. A given formless spawn can be large or small, but the average size is around 16 feet across with a weight of about 2,000 pounds.

The formless spawn, though technically oozes, almost never form simple shapes. They often sprout spindly legs to run upon, twisted faces to leer with, and limbs to grasp and hold. When lurking in a room, they commonly shoot out sticky strands to cling to the walls or ceiling, building a web-like structure out of their own bodies.

Despite their surface differences, the formless spawn are related to Tsathoggua himself and doubtless come from the same dark home. When Tsathoggua is wounded, he bleeds formless spawn so perhaps he is the ultimate goal and end-point of their life-cycle, or perhaps he is an aggregate construct the formless spawn created to house their magical potential.

Unlike many entities of similar influence, the formless spawn are wholly chaotic in their philosophy.

Though they sometimes work toward the same larger goal, each takes its own independent action and direction. Even Tsathoggua himself doesn’t try to command them, instead relying upon their own instinctual desires to work toward his schemes.

Section 15: Copyright Notice

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

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