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Yithian, Past

Past Yithian CR 14

This creature resembles a mollusk with an iridescent, vaguely coneshaped body about ten feet tall and a wide, snail-like foot. Four protrusions sprout from the dorsal side of the body: two claws, a grasping mouth, and some sort of horrific head bristling with sensing tentacles.

XP 38,400
LN Large aberration
Init +3; Senses blindsense 60 ft., darkvision 60 ft.; Perception +29


AC 29, touch 12, flat-footed 26 (+3 Dex, +17 natural, –1 size)
hp 207 (18d8+126); fast healing 5
Fort +15, Ref +9, Will +17
Defensive Abilities all-around vision; DR 10/magic; Resist acid 10, cold 10, fire 10


Speed 20 ft., climb 10 ft.
Melee 2 pincers +24 (2d8+18/19–20×3) or Ranged Yithian lightning gun +15 (10d8 electricity)
Space 10 ft.; Reach 10 ft.
Special Attacks amnesia, deadly pincers, mind swap
Spell-Like Abilities (CL 16th; concentration +20)

At willastral projection (self only), detect thoughts (DC 16), hold monster (DC 19), modify memory (DC 18)


Str 34, Dex 17, Con 25, Int 30, Wis 19, Cha 18
Base Atk +13; CMB +26; CMD 39
Feats Alertness, Combat Expertise, Great Fortitude, Improved Critical (pincers), Improved Great Fortitude, Improved Iron Will, Iron Will, Power Attack, Vital Strike
Skills Climb +20, Craft (any one) +28, Diplomacy +22, Disable Device +21, Heal +22, Knowledge (arcana) +31, Knowledge (engineering) +31, Knowledge (geography) +31, Knowledge (history) +31, Linguistics +28, Perception +29, Profession (Yog-Sothothery philosopher) +29, Sense Motive +26, Spellcraft +31, Use Magic Device +22
Languages Aklo, 20 other languages, Yithian; telepathy 100 ft.
SQ item creation, scholar


Amnesia (Su)

Once per day as a standard action, a yithian can attempt to inflict amnesia on a target it is able to communicate telepathically with. A target can resist this attack with a DC 23 Will save. If the target fails its save, it takes a permanent –4 penalty on Will saving throws and all skill checks and loses all memories save for those the yithian chooses to leave intact. This effect can be cured by heal or greater restoration. This is a mind-affecting insanity effect. The save DC is Charisma-based.

Deadly Pincers (Ex)

A yithian always applies 1-1/2 times its Strength modifier to damage dealt by its pincer attacks, and deals triple damage on a critical hit. Pincers are primary attacks for yithians.

Item Creation (Ex)

A yithian possesses the ability to create exotic and powerful items that blur the line between magic and technology, given time and resources. This ability allows a yithian to ignore all of the Item Creation feat requirements and spellcasting requirements for creating a magic item. The resulting item is always yithian technology (see sidebar), built for their claws and tendrils to manipulate.

Mind Swap (Su)

As a full-round action, a yithian can trade minds with another living creature it is able to communicate telepathically with. This functions as magic jar, except the two minds trade bodies. An unwilling target can resist the mind swap with a DC 23 Will save, after which that particular yithian cannot attempt to swap minds with that creature again for 24 hours. The yithian can end the effect of this mind swap at any time and over any distance as a full-round action, instantly returning both minds to the proper bodies; if the yithian wishes, it may attempt to use its amnesia power on the other mind as a free action when it ends the mind swap in this way. With the aid of singular technological devices, yithians can swap minds with targets in other times as well, although this procedure often leaves the traveling minds disoriented for a period, so yithians use it only under controlled conditions. This is a mind-affecting effect. The save DC is Charisma-based.

Scholar (Ex)

Yithians treat all knowledge skills as class skills.


Environment any
Organization solitary, pair, band (3–9), or enclave (10+)
Treasure standard (Yithian lightning gun [page 153], other treasure)

The “great race” was so-called because it was the only natural terrestrial species to conquer time and extinction. Rather than travel physically through time, those of the great race are known instead to project their minds across eons, swapping minds with members of their target species. This gives the great race an ideal means of studying other races and other times whilst avoiding easy detection, and it is also how the great race has escaped extinction. By its knowledge of all time, both future and past, it knows when its current form will become untenable. Before this happens, the great race transfers its minds—as a whole—to the chosen species, which then becomes its new form. Their victims have their minds sent back into the bodies of the great race: confused, shocked, and on the brink of extinction, where they speedily meet their doom.

Thus the great race, despite their glories, literally wipe out an entire species (at least mentally, culturally, and spiritually) each time they move on.

The Great Race of the Past

The true origin of the great race is lost to antiquity, but eons ago, they dwelt on a planet named Yith. As a result they are often called Yithians, but even Yith was not their original home. They once inhabited the bodies of large invertebrates with a massive brain capacity and great potential, and this is the form they are usually pictured in.

In their most recent incarnation, this species has a basically cone-shaped body and moves along on a complex foot like that of a mollusk. Near the top of the cone, four boneless limbs twists forth: two ended in sharpened powerful claws, one in a cluster of sense organs and delicate tentacles used for fine manipulation, while the last ends in cone-shaped tubes used for feeding. The creature’s huge brains were at the top of the cone, centered between the limbs. The great race is immensely intelligent: a typical specimen’s brain weighs over 200 pounds and is actually more efficient, neuron-for-neuron, than the human brain.

Yithians are massive—typically standing over 3 meters tall and weighing 4 or more tons—and very long-lived. of course, an individual Yithian can always evade death by mind-switching with another creature.

If a Yithian’s body is killed before it can switch minds, it does indeed die.

The great race tamed dinosaurs, pterosaurs, sea reptiles, and other primeval monsters, often controlling these beasts via electronic implants. Their preferred tools, however, were technological. They were not unified and often fought civil wars amongst themselves, as well as battling other powerful primeval species, such as the elder things, serpent folk, flying polyps, and starspawn.

Yithian Technology

Yithian items function similarly to established magic items, but while the mechanics may not change, the item’s appearance often varies quite drastically from the item it emulates. For example, a yithian lightning gun looks like a strange camera-like array of lenses and metal calipers, but functions in-game identically to a rod of thunder and lightning.

A yithian item can be identified in the same ways as any magic item, but its strange nature imparts a –10 penalty to the Spellcraft check to comprehend the item. At the GM’s discretion, after some time spent among yithians or studying their technology, a character can eventually remove this penalty.

Non-yithians have difficulty manipulating yithian items, and in order to activate such an item, a non-yithian must make a successful DC 20 Dexterity or Sleight of Hand check (in addition to any Use Magic Device check or other skill check that might be required). If the check fails, the item does not function and the action is wasted. If this check fails by 5 or more, the item backfires dangerously and unpredictably.

Other species have been known to emulate yithian craftsmanship: for instance, a mi-go can use Knowledge (engineering) to craft yithian technology.

Relationships with Humanity

The great race periodically sends scouts to take over human bodies in order to investigate and record human progress. They have fostered a sort of cult to assist them in this, and reward their followers with advanced knowledge and secrets from the entirety of time. Unfortunately, they are also preyed upon by enemies, such as the cult of the Yellow Sign, who try to capture members of the great race in human form, and torture them to gather their secrets.

In general, the great race acts as a neutral observer of human antics, but they may occasionally try to drive events in a direction which is beneficial to them.

Section 15: Copyright Notice

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