Aberrations

Akatas hail from a strange, distant planet that long ago succumbed to a cataclysmic end. Countless akatas clung to fragments of the dead planet, entering hibernation and riding these asteroids until they eventually crashed upon a new planet—akatas’ cocoons protected them from the impact, and they soon awoke to seek out suitable hosts to spawn their young. Left untended, an akata scourge can quickly grow into a significant threat.
A typical akata stands 3-1/2 feet tall and weighs 400 pounds.

Devised by a cabal of ancient wizards to serve as guardians for monuments and laboratories, shriezyx are horrific spiderlike aberrations created in arcane vats out of the flesh of many different creatures. Having outlived their creators, they continue to lurk in ruins, caves, and the deep places of the world, spreading far beyond the original city where they were created. Shriezyx have no natural place in the ecology, but easily fill the niche of any predator of comparable strength. They can subsist on rats and other vermin for long periods of time, but relish the opportunity for a more substantial meal. Derros, drow, and other subterranean races sometimes use them as guards or mounts, or subject them to torturous experimentation. These races use bribes of food and the threat of fire to keep the creatures in line. Shriezyx can reproduce with their own kind or lay unfertilized eggs that hatch into identical copies of their parent. Eggs remain viable for years, hatching after exposure to water, fresh air, or consistent warmth.
A typical shriezyx is 3 feet tall and weighs 300 pounds.

Lunar nagas are patient watchers of the night sky. They enjoy cosmology and believe strongly in astrology, maintaining a handful of complex zodiacs. A few lunar nagas even bear knowledge of the unspeakable things from the dark spaces between the stars.
Nocturnal creatures, lunar nagas often live in ruined towers or atop mountains— any place open to the sky at night. There they peer through astrological devices, closely monitoring passing celestial markers, eager to decipher more of the universe. Those living underground make nightly trips to the open sky when they can. Cloudy nights make lunar nagas agitated, and a creature is more likely to run afoul of a lunar naga on these dark evenings. Lunar nagas sometimes lead small cults of sky-watchers. These followers aid the nagas in recording tome upon tome of calculations of the stars and planets moving through the inky black of the night sky. In small doses tempered with water, fruit juices, and alcohol, lunar naga venom is mildly hallucinogenic. The nagas’ cultist allies often take the substance as a ritualistic drug.
A lunar naga stretches over 10 feet from its pale face to the tip of its tail, and weighs close to 200 pounds.

A rhu-chalik, also called a void wanderer, is an alien entity that scouts through space on behalf of its conquering masters. In addition, this aberration also collects the memories of interesting creatures in the universe into a vast repository of knowledge that their masters use to slowly unravel all the secrets of existence.  Rhu-chaliks serve their masters tirelessly, and are as patient as they are long-lived. They rarely make an uncalculated move, and seek only the most prized intellects to cast into the dark beyond for their masters’ delectations. When exploring distant worlds, rhu-chaliks are not social beings, and they avoid other rhu-chaliks so their predations won’t cause too much overlap in the mind collections of their masters. However, back in their native space, rhu-chaliks number in the billions, and the creatures feed off a countless number of disembodied minds.  
A rhu-chalik is approximately 3 feet across and weighs only 30 pounds.  

Aatheriexas were once a race of conquerors and slavers, but since the destruction of their homeworld, the survivors have wandered the cosmos. Exceedingly cruel, they find perverse pleasure in tormenting those they capture, using them as disposable bodyguards or subjecting them to sadistic magic experiments.  
An aatheriexa’s fleshy pink center is roughly 2 feet in diameter, and features a maw of gnashing teeth. Its grasping eye-tentacles hang down like the leaves of a weeping willow and extend its effective diameter to 5 feet. Aatheriexas weigh approximately 150 pounds.

As befits their hideous primeval appearance, the hermaphroditic aboleths are among the world’s oldest forms of life. Ancient even when the gods first turned their eyes to the Material Plane, the aboleths have always existed apart from other mortal life, alien and cold and endlessly plotting. They once ruled the world with vast empires, and today view most other forms of life as either food or slaves—and sometimes both. They disdain the gods and see themselves as the true masters of creation.
In the darkest reaches of the sea, aboleths still dwell in grotesque cities built in nauseating and cyclopean styles. There they are served by countless slaves culled from every nation, air-breathing and aquatic alike, although the air-breathing slaves are doubly bound by magic and the need to constantly replenish their water-breathing ability via the excretions of their aboleth masters. Lone aboleths are often advance scouts for these hidden cities, seeking out new slaves.
An aboleth is 25 feet long and weighs 6,500 pounds.

Known also as brain collectors, the alien neh-thalggus hail from distant worlds, traveling the gulfs of space on immense living ships that swiftly decay when they land upon a new world, leaving behind a deadly cargo of hungry monsters. Neh-thalggus are carnivores, but they do not digest humanoid brains they eat—rather, these brains lodge in one of several bulbous blisters on the creature’s back and help to increase its intellect. Some speculate that neh-thalggus encountered in this reality may merely be juveniles of their kind, perhaps exiled from their home worlds by greater kin until they can prove their worth on other worlds. Their brain collections may be a morbid form of currency in their home realm, or the thoughts in these brains may merely be fuel for a dark apotheosis into an even more sinister mature form.

Untold eons ago, the yithians inhabited a dying world. To escape their doomed planet, they cast their minds through time and space, eventually coming to rest in the strange, alien bodies they possess today. While these strange beings now reside in a distant galaxy, the yithians make use of their ability to astrally project to explore other planets, eager to find new worlds to explore. When a yithian arrives upon a new world, it often swaps minds with the creatures it encounters there so as to experience that world as if it were a native. Those who spend time in a yithian’s body rarely tell of the strange times they have experienced, for yithians guard themselves well, and leave those they use in this manner amnesiacs who remember the truth only as fragmentary nightmares.

When an especially powerful psychic leads a community of like-minded individuals, that group can pool its collective will together to create an egregore. The egregore is a powerful defender and a focal point for the psychic talents of every member of the group, granting them access to additional magical powers and a communal link. Though egregores’ appearances vary, they typically have a core that resembles a mass of brains, discernible by practitioners of phrenology as bearing characteristics of the brains of those who make up its cult mind. This core projects an image that reflects the ideals for which the egregore was formed—an unblinking eye to represent vigilance, a heraldic shield for protection, or some other stylized emblem to reflect the goals of the group. From this bizarre hovering mass emerges a number of pulsating arcs of light that move in a strange unison, forming an almost mesmerizing pattern with their cadence. The synchronized synaptic pulses that emit from the egregore’s cranial core manifest as elegant arcs of light leaping from one brain-shape to another in a rhythmic dance. The egregore can divert an arc outward, transforming it into a semi-solid band of light it can use to strike its foes. These bands normally pass through objects, but by concentrating more fully, the egregore can transform an arc into an even more solid form capable of manipulating objects.
Typically, the sort of cult that creates an egregore is formed of a small association of individuals under the guidance of a strong-willed psychic leader, who directs the weaker-minded followers in a ritual that combines their latent psychic energy into the creation of a powerful entity to support the goals of the organization.  The egregore itself is a totally separate creature, akin to the eidolons of summoners, though it seems to be a genuine living being of the Material Plane and not a true outsider. Creating an egregore requires a cult of 13—one leader and a dozen followers. Larger cults are capable of creating more powerful egregores, with stories circulating of doomsday cults with hundreds of members working together to create an abomination, but subsequently losing control and facing annihilation from their own creation. The egregore exists only as long as the cult that created it, fading back into the psychic ether from which it spawned once the cult is no more.  
An egregore is 12 feet across, though the bands of light that extend out from it cause it to fluctuate between an effective size of 13 feet to 15 feet. It weighs only 300 pounds despite its vast size. The brains that make up the egregore’s body aren’t constructed like human brains, and are far less dense; they seem to take the form of brains only because of the conceptual link they represent. Likewise, the egregore’s staring eye and bands of light are more metaphorical than physical.

Leng hounds hail from the nightmare plateau of Leng, where they haunt its eternity-old ruins. They are most often beckoned to the Material Plane to serve as guardians of grave sites, a duty they eagerly perform in exchange for the opportunity to feast upon the dead things elsewhere in the cemetery. Leng hounds prefer to lurk inside the coffins they guard, rearranging their bodies into skeletal shapes.  A Leng hound can be contacted by a contact entity III spell. The caster must provide a corpse with grave goods worth at least 2,000gp for the Leng hound to guard.  
A Leng hound is 7 feet tall but weighs only 150 pounds.

Trench mists arise from the wholesale slaughter of troops with spells such as acid fog and cloudkill. These magical mists linger over the battlefield, absorbing the departing souls and mental anguish of the slain, and developing a supernatural, malevolent sentience. Once born, trench mists seek only to impart misery and inflict a choking, scalding fate on those fortunate enough to escape the attacks that birthed the creature in the first place.  As it preys upon the living, a trench mist bleeds its bitter impulses into those it kills, adding the afflicted to a growing horde of shambling servants. Victims of its acidic mist rise as hateful zombies under the creature’s control, and a trench mist that gains a horde of zombies is a dangerous foe indeed. On battlefields where trench mists are known to have arisen, wise commanders arrange cease-fires during which both sides abandon the site after gaseous attacks, lest their troops succumb to the horrifying fate of their comrades.  
A trench mist’s billowing form extends 20 feet across, but if bottled, weighs less than a pound.

Moon-beasts have no voice or eyes, yet they “see” more than most and can project their thoughts into the very minds of those they wish to communicate with. These monstrosities hail not from any physical moon, but rather from the shared satellite of all slumbering minds in the Dimension of Dream beyond the wall of sleep. Here, the moon-beasts raise stone cities on the oily shores of nightblack seas found upon the dark side of the dreaming moon, from which they launch long, dark galleys crewed by not-quite-human slaves that sail through the void of space down to the seas of the Dimension of Dream to seek new slaves and stranger, more sinister wares. Moon-beasts are slavers, first and foremost. They use their spell-like abilities to curb rebellion or to quickly gain minions, but much prefer using physical and mental regimens of torment and reconditioning to break the spirit of their captives. They often work with the denizens of Leng, a metaphysically nearby dimension of nightmare and madness, although as often as not these planar neighbors serve the moon-beasts merely as slaves. Worshipers of ageless entities from beyond the stars, moon-beasts are often compelled to travel to the Material Plane for strange and frightening causes, not the least of which is gathering suitable sacrifices for their mysterious and demanding lords.
A moon-beast is 9 feet long and weighs 800 pounds.

Serpentfolk breed syrictas by performing a ritual to infuse a deformed serpentfolk egg with the vital essence from a clutch of snake eggs. The resulting amalgamation is a nightmarish cross between a serpentfolk and a mass of writhing ophidian tails and heads.  Numerous snakes make up these abominations’ lower halves, granting them a slithering form of locomotion. Each syricta also has a thick, muscled snake tail forming one of its arms, allowing it to wrap around prey and squeeze the life from them, while its other arm splits at the elbow into two venomous snake heads, granting the syricta a total of three deadly bites. Despite being much smaller than its main head, the arm heads are possessed of unexpected strength for their size, making them equally deadly. These heads are also adept at manipulating objects, allowing the syricta to perform any action that would require a hand—such as holding a weapon—at the expense of those bite attacks.  These hideous monstrosities serve the serpentfolk as bodyguards and enforcers, their primitive minds conditioned to obey their serpentfolk masters. They fight to the death if so commanded, though when they lack commands from a serpentfolk, they act as brutish bullies and cowards, viciously and sadistically harming those weaker than themselves but fleeing from foes that prove stronger.  Syricta societies are harsh, ruled absolutely by the strongest individuals, and rarely last long due to syrictas’ inability to reproduce. Most syrictas instead spend their lives serving their serpentfolk creators, rarely forming relationships with other syrictas. Syrictas are entirely carnivorous.
A typical adult syricta stands around 9 feet tall and weighs 550 pounds.

An argus is an ancient creature related to the titans, transformed by a deity into a vigilant and restless sentry, usually as a punishment for some affront or rebellion. Within its hideous and misshapen body lies a lonely heart that craves music and beauty to comfort it in its forlorn and unending vigil. It might talk peaceably with visitors if they promise to sing songs or tell stories (and it believes its guests don’t intend to harm it or steal what it guards). If insulted or mocked, an argus is quick to anger, dispatching foes so it can go back to brooding in peace.
An argus stands 25 feet tall and weighs 18,000 pounds.

A flying polyp is a nauseating mass of flesh, eyes, tentacles, and mouths. These creatures seem to have no maximum lifespan, but their violent, warlike nature ensures that death eventually occurs—even if it takes eons for the polyp to encounter something capable of defeating it. A flying polyp is a physical being, but one composed of material strangely unlike the flesh that garbs most living creatures. While the stuff that makes up the exterior of a flying polyp’s body might seem similar to ordinary flesh, it often behaves in ways that should be impossible. The material seems to fade in and out of visibility, almost at random, at points becoming transparent enough that the nauseating inner workings of the thing’s body are laid bare. Although the polyp feels moist and damp to the touch, what might serve as blood in other creatures behaves more like strange vortices of wind within a flying polyp’s body. When wounded, its damaged flesh does not bleed so much as whistle and gust.
A flying polyp’s association with wind goes far beyond the strange storms that surge through what pass as veins and arteries in its massive body. These creatures have a remarkable ability to control the air around them, both via a wide array of spell-like abilities and through the use of potent supernatural powers. They do not wield tools or weapons as a rule, instead using their mastery of the winds themselves to wage war and build their grim cities, scouring towers and chambers out of basalt with precise blasts of sand-laden wind.
Although flying polyps display some of the features of other sentient races, particularly in their habit of building cities (although these towering settlements usually incorporate architectural features that most other races find awkward and unsettling), in other areas they seem strangely primitive or uninterested. They are as aberrant in mind and philosophy as they are in physical form. For example, they seem to have neither a name for their own race, nor a language to call their own. Their cities, while bewildering in their vast scale, seem to serve little purpose other than to unnerve, for flying polyps do not engage in trade or politics or other social constructs. The primary exception to this, to the detriment of other creatures unfortunate enough to dwell in regions claimed by flying polyps, is war. Flying polyps excel at genocide, using their mastery over wind to scour clean entire cities and civilizations when they come upon them. Some among their kind can even travel to other planets by bringing with them a sizable sphere of purloined wind to carry them aloft and sustain them, and with this power they lead armies from planet to planet as necessary, relentlessly tracking their chosen enemies across worlds. Every so often, flying polyps encounter a race that is their equal in war, and on some worlds, they still endure the humiliation of these ancient defeats after being imprisoned in extensive underground chambers where they are cut off from the outside world. Yet flying polyps are long-lived, and should unforeseen tectonic events creates new exit to their prison chambers, lost in the forgotten corners of those planets’ depths, they emerge with unabated fury to seek revenge against the enemies who dared humiliate them so.
A typical flying polyp measures 30 feet in length but is unusually light for its size, weighing no more than 2,000 pounds.

Though conqueror worms resemble immense vermin, those who mistake them for mindless creatures suffer terribly for their mistake. In truth, conqueror worms are creatures of vast intellect and equal depravity. These monstrous beings exist only to rule “lesser civilizations” from the shadows, and revel in the complete control of an unknowing society through the remote manipulation of its supposed leaders.  A conqueror worm prefers to play with its toys before breaking them. To do so, it burrows its way below a target nation’s capital. From there, the conqueror worm makes mental contact with the city’s leaders, forming sinister psychic connections with those in power. The worm beguiles some of these leaders with promises of wealth or power. Others, the worm controls outright using the considerable psychic magic at its disposal. Regardless, the end result is the same; without intervention, all end up as puppets dancing to the conqueror worm’s whims.  Once a conqueror worm seizes control of a city or nation, that region’s downfall can take years, if not decades—for conqueror worms are surprisingly theatrical. A conqueror worm may direct a kingdom’s leader to enact cruel or tyrannical laws, only to then use a second puppet to inflame the populace into revolt. Once the fires of revolution die down, the worm might then expose the rebel leader as a traitor or depraved criminal, causing the rebellion to turn on itself and descend again into violence. All the while, the conqueror worm watches in delight at the madness, sin, and horror it inspires in others.  Eventually a conqueror worm tires of its games, and plots to destroy its subjects. Often it does this by sending its puppets to war against a nearby nation. The horrors of war devastate not only the worm’s own populace, but also those of its neighbors, bringing perverse joy to the worm’s many hearts. However, a special fate awaits the worm’s favorite servants, who are brought down into its subterranean realm so they can glimpse their master’s true form before being impaled on the conqueror worm’s gore-slick jaws. Its work finally finished, the conqueror worm then seeks out a new realm to subjugate.  Perhaps the most terrifying and peculiar aspect of the conqueror worm is its ability to form cults. Whether through accumulation of psychic power or some hidden divine spark, conqueror worms are capable of granting spells to creatures that worship them. A conqueror worm exploits this ability to attract cultists, which it uses to further its goals in the civilized world above. Although such cults are absolutely loyal to the conqueror worm, which they worship as an all-knowing and all-powerful god, the conqueror worm usually considers its mortal followers expendable.  
A conqueror worm is 80 feet long and weighs 70 tons.

Primal life energy, raw and uncontrolled, seethes through this mother of monsters. Her churning, distended belly mocks creation, birthing horrors and dismal failures. The weak are torn apart in the writhing mass of her nursery, while the strong transcend their hideous origins to become creatures of greatness in their own right. She is always encountered with at least a handful of her favored children, as well as other progeny she can sacrifice to protect herself. With their help, she impregnates those who come across her with twisted, monstrous life.