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Great Old One

Source Bestiary 4 pg. 135
The Great Old Ones are otherworldly entities of almost unimaginable power—beings completely alien to humanity, both physiologically and spiritually. They exist in the forgotten corners of distant worlds or lost dimensions, yet their power is so great they can inf luence certain sensitive mortal minds in their dreams and nightmares, even if such inf luence is as accidental as a star’s gravitational pull on a tiny mote of dust adrift in space. In such ways, cults devoted to the Great Old Ones can rise on worlds throughout the Material Plane, even without prior contact between these worlds. Some of the Great Old Ones grant access to the domain of Void and its associated subdomains (see below).

While not all of the Great Old Ones are evil, all are forces of chaos. Their cults are almost always evil and cause harm and madness, but the Great Old Ones are generally content to ignore lesser life such as humans, elves, and dwarves. Yet when their attention is garnered, the results can be catastrophic on an immense scale— for just as the ant who bites someone’s toe invites swift destruction on a scale its feeble mind can’t envision, so too does humanity invite unimaginable ruin by delving into the affairs of these powerful creatures.

The Great Old Ones themselves often serve and worship even greater powers, such as Azathoth, Nyarlathotep, Shub-Niggurath, and Yog-Sothoth. Those creatures are the Outer Gods, and whereas the Great Old Ones can be thought of as akin to demigods, the Outer Gods are themselves true deities.

Other Great Old Ones

Bokrug, Cthulhu, and Hastur are but three of the Great Old Ones—countless others exist on distant worlds or other dimensions, yet are still able to influence the world through their dreams and cults. The central concept of the Great Old Ones was created by H. P. Lovecraft, one of the most influential writers of weird fiction—and horror fiction in general—of the 20th century. Lovecraft actively encouraged his writer friends to add to his mythos of creatures, and today we have Great Old Ones created not only by Lovecraft’s contemporaries like Clark Ashton Smith, Robert E. Howard, Henry Kuttner, and August Derleth, but also by modern writers like Ramsey Campbell, Brian Lumley, and Stephen King. Chaosium’s excellent Call of Cthulhu roleplaying game is a perfect place to start delving into the realm of Great Old Ones evoked in RPG form. By creating new Great Old Ones for your game, you can become part of a tradition of shared mythology nearly a century old!

Creatures in "Great Old One" Category

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Great Old One, Atlach-Nacha

The size of a bull elephant, this red-and-black arachnid has a bloated body and spindly legs, made all the more horrifying by the all-too-human appearance of its baleful visage.

Atlach-Nacha CR 28

Source Pathfinder #112: The Whisper Out of Time pg. 84
XP 4,915,200
NE Huge aberration (evil, Great Old One)
Init +23; Senses darkvision 60 ft., see in darkness, true seeing; Perception +46
Aura unspeakable presence (300 ft., DC 35)


AC 46, touch 32, flat-footed 32 (+13 Dex, +1 dodge, +10 insight, +14 natural, –2 size)
hp 688 (32d8+544); fast healing 25
Fort +27, Ref +23, Will +29
Defensive Abilities freedom of movement, immortality, insanity (DC 35); DR 15/epic and lawful; Immune ability damage, ability drain, aging, cold, death effects, disease, energy drain, mind-affecting effects, paralysis, petrification, poison; Resist fire 30, sonic 30; SR 39


Speed 80 ft., climb 80 ft.
Melee bite +39 touch (4d10+25/19–20 plus poison), 4 claws +39 (3d6+25/19–20)
Ranged web +35 touch (special/×3)
Space 15 ft., Reach 15 ft.
Special Attacks critical poisoning, dreams of futility, feed, mythic power (10/day, surge +1d12), penetrating bite, poison, powerful blows, webs (DC 43, 32 hp)
Spell-Like Abilities (CL 28th; concentration +37)
Constant—feather fall, freedom of movement, true seeing
At will—astral projection, dimension door, dream, greater dispel magic, insanity (DC 27), levitate, nightmare (DC 24), sending, telekinesis (DC 24)
3/day—creeping doom, demand (DC 27), quickened feeblemind (DC 24)
1/day—imprisonment (DC 28), symbol of insanity (DC 27), dominate monster (DC 28)


Str 44, Dex 36, Con 44, Int 29, Wis 33, Cha 28
Base Atk +24; CMB +43 (+47 bull rush); CMD 77 (79 vs. bull rush)
Feats Awesome Blow, Combat Reflexes, Critical Focus, Dodge, Greater Bull Rush, Greater Vital Strike, Improved Bull Rush, Improved Critical (bite), Improved Critical (claw), Improved Vital Strike, Mobility, Power Attack, Quicken Spell-Like Ability (feeblemind), Spring Attack, Staggering Critical, Vital Strike
Skills Acrobatics +48 (+88 when jumping), Climb +60, Intimidate +44, Knowledge (arcana, dungeoneering, history, religion) +41, Perception +46, Sense Motive +43, Spellcraft +44, Stealth +40, Survival +46, Use Magic Device +41; Racial Modifiers +40 Acrobatics when jumping
Languages Aklo, Undercommon; telepathy 100 ft.
SQ otherworldly leap, swift construction


Environment any underground
Organization solitary (unique)
Treasure triple

Special Abilities

Critical Poisoning (Su) If Atlach-Nacha confirms a critical hit with its bite, it injects its foe with 3 doses of poison (this increases the save DC by 4). A foe that is normally immune to poison can be affected by Atlach-Nacha’s poison in this way, but the victim treats the poisoning as if it had been injected with only 1 dose.

Dreams of Futility (Su) Atlach-Nacha can impose its verminous dreams on any creature that has been rendered unconscious at any point in its life as a result of spider venom, that has come in contact with the Great Old One’s webs, or upon whom Atlach-Nacha has fed. When Atlach-Nacha uses nightmare on such a target, the victim must also succeed at a DC 35 Will saving throw or become overwhelmed with futility. Whenever the victim attempts a skill check, or at the start of each round in combat, the victim has a 50% chance to act normally; otherwise, it takes no action. This effect persists for 24 hours but can be ended earlier via a successful break enchantment spell. This is a mind-affecting effect. The save DC is Charisma-based.

Feed (Ex) As a standard action, Atlach-Nacha can feed upon a helpless or willing living creature by biting it. This deals no hit point damage, but it does cause 2d6 points of Strength drain and 2d6 points of Dexterity drain. If a creature’s Strength and Dexterity are drained to 0, any drain that would normally affect those ability scores instead affects Constitution—thus, if Atlach-Nacha feeds on a creature with Strength and Dexterity scores of 0, the Great Old One drains 4d6 points of Constitution instead. A successful DC 43 Fortitude save reduces the drain to the minimum possible. The save DC is Constitution-based.

Great Old One Traits Rules for Atlach-Nacha’s Great Old One traits, such as immortality, insanity, its mythic abilities, otherworldly insight, and the base rules for unspeakable presence, can be found on page 306 of Pathfinder RPG Bestiary 4.

Immortality (Ex) If Atlach-Nacha is killed, its body splits open and unleashes a hideous mass of swarming spiders. Treat this swarm of spiders as a locust plague swarm (Pathfinder RPG Bestiary 5 192) save that it has a base speed of 60 feet, a climb speed of 60 feet, and no fly speed. If this swarm of spiders is allowed to reform after being dispersed by damage (or after 24 hours have passed), the spiders fall upon one another in a cannibalistic frenzy, with the last spider alive growing and growing until it becomes Atlach-Nacha reborn. If the swarm is truly destroyed as a result of devouring a good-aligned minor artifact or holy relic, Atlach-Nacha is instead reborn 1d100 months later from one of countless hidden eggs in deep underground caverns— but typically not on the same world upon which it was most recently defeated.

Otherworldly Leap (Ex) Atlach-Nacha gains a +20 racial bonus on Acrobatics checks made to jump, and this stacks with its bonus to jumping from high speed. It treats all jumps as if it had a running start.

Penetrating Bite (Ex) Atlach-Nacha’s bite penetrates all forms of armor. It resolves its bite attacks as if they were touch attacks.

Poison (Ex) Bite—injury; save Fort DC 43; frequency 1/round for 6 rounds; effect permanent paralysis plus 1d6 Strength drain; cure 3 consecutive saves. The save DC is Constitution-based.

Powerful Blows (Ex) Atlach-Nacha always modifies the damage from its physical attacks with 1-1/2 times its Strength modifier.

Swift Construction (Ex) Atlach-Nacha can create bridges or walls from its webs as a swift action. A web bridge is 15 feet wide and has a maximum length of 200 feet. A web wall functions as a wall of stone (CL 20th). Atlach-Nacha can use its climb speed to move on these webs, but other creatures treat it as sticky webbing (see the web universal monster rule on page 305 of Pathfinder RPG Bestiary) if they come in contact with it. Atlach-Nacha’s web constructions collapse and melt into vapor after 1 day has passed, forcing the Great Old One to constantly toil to maintain its webs in a futile effort at permanence.

Unspeakable Presence (Su) Failing a DC 35 Will saving throw against Atlach-Nacha’s unspeakable presence causes victims to become convinced they are covered with swarming spiders and tangled, sticky webbing. This causes victims to become nauseated for as long as the Great Old One remains in the area plus an additional 1d6 rounds. This is a mind-affecting effect. The save DC is Charisma-based.

Webs (Ex) Atlach-Nacha can make a ranged attack with its webs as a swift action. These webs have a range increment of 200 feet, and it can shoot up to 10 range increments.


This strange arachnid Great Old One, known to some as the Void Weaver, is a dualistic entity in many respects. Its gender is fluid, being both and neither male and female. It constantly toils to build, yet its creations are fated to fail. It exists both in the waking world and the realm of dreams. It embodies the alien form of the spider and the recognizable visage of humanity. To Atlach-Nacha, duality exists only to contradict itself.

Atlach-Nacha is an elephant-sized, red-and-black spider with a monstrously humanoid face, but at times it can appear as a woman with multiple long arms and a spider’s lower torso.

Atlach-Nacha’s Cult

Atlach-Nacha’s worshipers venerate the spider god in a oddly dualistic way—as both a god of construction and a god of futility. To the Void Weaver’s faithful, the act of building is as sacred as the act of deliberately allowing something to fail. Whether this is to create more opportunities for building or more opportunities to fail is irrelevant to these lunatic worshipers, who vacillate daily between the urge to create and the compulsion to give in to entropy and disorder. Atlach-Nacha’s temples are often caves or ancient crumbling buildings infested with spiders. The Great Old One grants access to the domains of Artifice, Evil, Madness, and Void and to the subdomains of Construct, Isolation (Pathfinder Campaign Setting: Inner Sea Gods 225), Nightmare, and Toil. Its favored weapon is the net.