Sandy Petersen's Cthulhu Mythos - Pathfinder


CR 18; XP — (see Combat)
NE Great Old One of construction, futility, and spiders
Primary Source Clark Ashton Smith, “The Seven Geases”


Domains Artifice, Evil, Madness, Void
Subdomains Construct, Isolation, Nightmare, Toil
Favored Weapon net
Symbol spider perched in the center of a web
Temple caverns, chasms, bridges
Worshipers doomsayers, mad architects, spider cultists
Servitors giant spiders and oversized arachnids

Influence Stage 1 (DC 25)

Area 20-ft. radius; Nucleus 20 square feet (fills entire area)
AC 33; Saves +20; hp 300
Effects webs
Escalation Destroying the influence has an increasing chance of instead escalating the influence to stage 2; see “Webs” below under Influence effects.

Influence Stage 2 (DC 27)

CR 21; XP 409,600
Area 400-ft. radius
Proxy avatar
Effects webs


Combat At stage 1 influence, Atlach-Nacha can be destroyed by damage, but doing so doesn’t prevent his cultists or other existing conditions or events from causing new influences to manifest elsewhere. As a result, defeating the stage 1 manifestation of this influence does not remove the continuing threat, and no XP reward is earned for this accomplishment (although defeating foes that might dwell in the region earns XP as normal).

Once Atlach-Nacha’s influence grows to stage 2 and the spider god sends an avatar to investigate the damage to its webs, defeating the avatar causes all of Atlach-Nacha’s influences in that world to vanish and prevents new influences from forming for many years (or until cultists successfully perform the dangerous and complex rituals needed to reestablish contact with Atlach-Nacha). This success earns XP as normal for the Great Old One’s stage 2 influence.

Influence Effects

Webs Atlach-nacha’s initial influence is immobile and makes no attacks; he manifests only as a thick tangle of immense spider webs in one or more twenty-foot radius rough spheres. Often, Atlach-nacha maintains multiple separate influences in an area, particularly in regions where his cult is active. These separate influences never overlap but can be adjacent. The webs that fill the area of influence create difficult terrain, and every time a creature enters the area or begins its turn in the area, it must make a successful Reflex save to avoid becoming entangled.

The webs in an area of influence remain until they are destroyed by reducing that influence to 0 hit points, but each time an area of Atlach-Nacha’s influence is destroyed in this way, there’s a cumulative chance that the area of influence is immediately re-established at stage 2. The chance of this occurring is equal to 1% per area of influence destroyed by intelligent non-cultists of Atlach-Nacha. (Those who venerate the Great Old One cannot escalate an influence by destroying webs, nor can creatures that possess an Intelligence of 2 or less.) This chance is cumulative for an entire world: if ten groups of adventurers destroy ten webs over the course of ten years, for example, the next group to destroy webs has an 11% chance to escalate the influence to stage 2.

The starting percentage chance of this occurring when a group of PCs encounters the influence for the first time is subject to the GM’s preference, or could simply be set by rolling 1d100–1, with a result of 0 indicating that either this is the first time the influence has occurred in the world, or that the previous influence resulted in a shift to stage 2 before Atlach-Nacha was defeated.

Avatar of Atlach-Nacha (CR 21)

XP 409,600
NE Huge aberration
Init +15; Senses see in darkness, tremorsense 120 ft., true seeing; Perception +34


AC 38, touch 20, flat-footed 26 (+11 Dex, +1 dodge, +18 natural, –2 size)
hp 402 (23d8+299)
Fort +20, Ref +18, Will +21
Defensive Abilities freedom of movement; DR 15/epic and lawful; Immune ability damage, ability drain, aging, cold death effects, disease, energy drain, mind-affecting effects, paralysis, petrification, poison; SR 32


Speed 80 ft., climb 80 ft.
Melee bite +30 (4d6+15/19–20 plus god venom), 8 legs +25 (1d10+7/19–20)
Space 15 ft.; Reach 15 ft.
Special Attacks god venom, mastery of magic, swift webs, web (+26 ranged, DC 34, 23 hp)

Spell-Like Abilities (CL 21st; concentration +30)
Constant—feather fall, freedom of movement, true seeing
At will—dimension door, greater dispel magic, levitate, nightmare (DC 24), telekinesis (DC 24)
3/day—creeping doom, demand (DC 27), quickened feeblemind (DC 24)
1/day—imprisonment (DC 28), symbol of insanity (DC 27)


Str 40, Dex 32, Con 37, Int 23, Wis 26, Cha 29
Base Atk +17; CMB +34 (+36 overrun); CMD 56 (58 vs. overrun, 68 vs. trip)
Feats Combat Reflexes, Critical Focus, Dodge, Improved Critical (bite), Improved Critical (legs), Improved Initiative, Improved Overrun, Mobility, Power Attack, Quicken Spell-Like Ability (feeblemind), Spring Attack, Staggering Critical
Skills Acrobatics +37 (+57 when jumping), Climb +49, Knowledge (arcana) +32, Knowledge (dungeoneering) +29, Knowledge (history) +29, Knowledge (religion) +29, Perception +34, Spellcraft +32, Stealth +29, Use Magic Device +32
Languages Aklo, Undercommon; telepathy 100 ft.

Special Abilities

God Venom (Ex) Atlach-Nacha injects the god venom with a successful bite. This venom can affect creatures normally immune to paralysis or poison, but possessing either immunity does grant a +4 bonus to the save to resist the effects.

God Venom: Bite—injury; save Fort DC 34; frequency 1/round for 6 rounds; effect permanent paralysis; cure can only be cured via magic. The save DC is Constitution-based.

Legs (Ex) Atlach-Nacha’s legs are secondary attacks that inflict piercing and slashing damage.

Mastery of Magic (Sp) Once every 1d4 rounds, Atlach- Nacha may cast any sorcerer/wizard spell that has a casting time of 1 round or less and has no expensive material components as a spell-like ability.

Swift Webs (Ex) Atlach-Nacha may use its web ability at will as a swift action.

Atlach-Nacha is the spider-god, which is not the same as saying he is the god of spiders. Rather, he is a dire entity in the form of a spider. The object of his toil is to spin the Forever Web.

Physically, Atlach-Nacha resembles a monstrous spider to the untutored eye, but any expert can detect many significant differences. Atlach-Nacha can be encountered by summoning him with the proper rituals, or his wrath can be invoked by attacking his web too assiduously. While Atlach-Nacha realizes that the Forever Web must undergo some degree of weathering and wear, he is aware of every iota of damage, and if anyone or anything (for example, misguided adventurers) prove too dedicated to thwarting his work, he will scurry across the remaining strands of the web to confront them personally.

The Forever Web

This web stretches throughout all of the world’s key points and ley lines. Sometimes it passes through other dimensions and sometimes it makes a physical appearance in the material world. When the Web is complete, the strands activate, surging with energy, and the entire world collapses into a singularity, ending it all. It is not clear what happens after that moment, but some believe that Atlach-Nacha, at that point, will eat the now-tiny world, and digest all of the souls caught therein. Others claim that Atlach-Nacha will present the world as a new gem for the necklace of some supreme entity. Until the Forever Web is completed, no one can say except Atlach-Nacha.

Fortunately, the Forever Web takes eons to spin, and individual strands can be attacked and cut without much trouble. Atlach Nacha’s webbing is only sticky where he chooses to make it so in order to tangle prey, for example, or to secure an attachment on the side of a precipice.

Atlach-Nacha in Combat

Atlach Nacha constantly flings web strands at his foes, which tangle and eventually immobilize them. Atlach-Nacha can strike out with all eight legs, but his legs are not his primary attack means. He knows all spells and can sometimes cast while also attacking physically. In addition, Atlach-Nacha’s bite injects the god venom, which almost nothing can resist. Once injected, the venom inflicts almost immediate total paralysis, and is even able to immobilize other entities of god-like status.

This website uses cookies. See the Legal & OGL page for important information. Any material NOT covered by the Open Game License Version 1.0a is covered by the Creative Commons Attribution-ShareAlike 3.0 License.