Born from the Spelljammer campaign setting, the race of aberrations known as the neogi are the most-loathed race in the cosmos. Beholders might be dicks, but they mostly try to exterminate one another rather than anyone else, and get one on his own long enough and he'll turn into a pretty chill guy. Mind flayers may eat literal brains, but they'll at least refrain from doing it in front of you, and can be bought off with slaves or other valuable things.
But the neogi have no friends, for very good reason. Looking like an ugly, halfling-sized mixer of a moray eel and a wolf-spider, the neogi mind cannot conceive of any relationship between two other forms of sapient life that isn't owner and slave. Even aboard their own ships, there is a looooong human centipede of ownership that ends in slaves. Indeed, this is why they're less dangerous than they could be: it's really difficult for them to cooperate amongst themselves on any meaningful level without a whole lot of captains getting killed and eaten in brutal deathmatches for overlordship of multiple vessels.
Meanwhile, since they have no planet and probably blew their old one up, they jam around the universe voiping into crystal spheres to grab as many slaves as they can before voiping out. They don't even trade for them, because they can't conceive of the idea of two equal parties trading goods. The lone exception appears to be the illithids, and even they don't like hanging with the neogi.
Culturally, like mind flayers, they like palling around with Umber Hulks. Every adult neogi has at least one umber hulk slave, because they are slaves until they can enslave a neogi of their own. Biologically, they reproduce every bit as horribly (and hilariously) as one would expect from such a disgusting race. Once one of them starts getting a bit senile, they fucking poison him until he's a bloated lobotomized wreck called a Great Old Master that can do nothing but eat and eat and eat, until he falls over dead and a couple-dozen newborn neogi explode out of him, eating up all his remains and then one another. How bloated? They go from Small sized to Huge sized.
Comically, this means lone neogi are almost always renegades who don't want to be turned into literal baby-factories, chased by ships full of their kinsmen out to make them do their duty to their race and make more neogi. Combat-wise, they mostly rely on their umber hulk body guards, though their bite carries a slowing poison and every one in a couple of them dabbles in magic. The Great Old Masters, meanwhile, are slow and dumb, but fire or slashing damage causes newborn neogi to explode out of them and attack their attackers. Their ships are the charmingly-named Deathspider and Mindspider, and are hard to get because everyone hates them and attacks them on sight.
Amazingly, neogi were actually given something of a player character treatment in AD&D, despite how hideously evil they are! Precisely why PC stats for neogi appeared in Dragon Magazine #214's "Ecology of the Neogi" (a follow-up to Dragon #184's "Magic With An Evil Bite", which provided a brief selection of neogi-devised spells and magic items, as well as stats for the Umber Hulk Flesh Golem), who can say? In fact, they were so underdeveloped that it's perhaps more an example of 3e style "monster advancement" rules. Still, 1d4chan provides once again:
The rest of their powers must be extracted from their monster writeup.
Despite their incredible arrogance, the "Ecology of the Neogi" in Dragon Magazine #214 states that neogi do have a form of religion, although it's a warped and brutal one. What that article says is shared below:
The only neogi fable of interest to sages details the neogi creation myth. Their legends claim the universe was created by a Being named Ka’jik’zxi. This deity constructed the Planes, Spheres, Flow, and the planets. Finally it created five more deities, each like itself only weaker. The five, named Thrig’ki, P’kk, T’zen’kil, Kr’tx and Kil’lix, each represent one of the desirable aspects of the neogi race. These deities squabbled over their areas of control until Ka’jik’zxi grew tired of their bickering and punished them. Furious, the five hatched a plot to kill Ka’jik’zxi. Concocting a fatal brew with the “foulest ingredients” (including friendship, mercy, and compassion) they poisoned their Creator. Ka’jik’zxi swelled up to a huge size, and the young deities hid, fearful of Ka’jik’zxi’s wrath. Suddenly, Ka’jik’zxi burst, spilling its entrails across the spheres. Some landed in the Outer Planes—the parts containing mercy and compassion became the gods of good. Some of Ka’jik’zxi landed in the Lower Planes and became the evil gods. Ka’jik’zxi’s brain landed in a forgotten Crystal Sphere.
After much searching, the neogi deities found the brain. There they were amazed to discover life—the first neogi had been “born.” The deities taught the neogi of the multiverse and their destiny to conquer. The neogi built ships and left their homeworld—referred to in legends as Ka’jk’z. They have never returned, but the neogi know their mission: to conquer all the Spheres.
One in 20 neogi has priestly abilities, and each spelljamming vessel is overseen by at least one priest. Priests are permitted to add the word ki’zid after their name, meaning “favored of deities.” The Powers of the neogi are referred to as “deity” and not “god’ or “goddess,” as there is no distinction between male or female amongst the sexless neogi. Deities are viewed as servants by the insolent neogi, who continually demand favor and good fortune. Neogi never pray, and rarely offer sacrifice, since they see themselves as more important.
Pronouncing the name of a neogi deity incorrectly is an invitation to be killed slowly and painfully. Humans, who tend to find neogi pronunciation difficult, are advised not to attempt saying deities’ names. There are five neogi deities:
Thrig’ki (lesser power), Align: NE, Plane: Karish (Abyss), Portfolio: “love” (envy/jealousy)
- Although the deity of “love,” Thrig is better translated as jealousy or hatred. To neogi, jealousy and love are the same. Thrig’ki appears as a neogi with writhing snakes for hair and twelve spidery legs.
P’kk (lesser power), Alignment: LE, Plane: Ki’pik (Baator), Portfolio: fear, tyranny.
- P’kk is the favorite deity of captains and neogi in positions of power who enjoy bullying and manipulating their lessers. P’kk is seen as an umber hulk with the head of a neogi.
T’zen’kil (lesser power, Alignment: NE, Plane: Karish, Portfolio: torture, pain, suffering.
- The name of T’zen’kil is invoked by neogi torturers and those in charge of the slave pens. Worshippers are tattooed with grotesque black symbols of pain. T’zen’kil looks like a black neogi with a whip for a tongue.
Kr’tx (lesser power), Alignment: CE, Plane: Jik’qu (Gray Waste), Portfolio: war, brutality, strength.
- Kr’tx is the neogi deity favored by umber hulk slaves, who delight in brutality and wanton destruction. The favor of Kr’tx is always demanded before a major battle. Kr’tx is seen as a red neogi with continually burning claws and hair.
Kil’lix (lesser power), Align: LE, Plane: Karish, Portfolio: death, murder, poison.
- Kil’lix is the patron of murderers and assassins in the neogi world, and is seen as the darkest of shadows. Its horrid laugh is high-pitched and whining, yet also deep and booming, and is said to be heard by those who are about to die.
All neogi priests gain access to the same spheres of spells. Major access: All, Astral, Charm, Combat, Elemental, Healing (reversed only), Necromantic, War. Minor access: Protection, Summoning.
In Dragon Magazine #184, the article "Magic With An Evil Bite" introduced a number of neogi-crafted magical spells and items, which 1d4chan is generous enough to repeat here for you.
Venom bite (Evocation)
- Level: 2
- Components: V,S
- Range: 5 yds. + 5 yds./lvl.
- CT: 1
- Duration: Instant.
- Save: Special
- Area of Effect: 10' square
This spell is the neogi version of a magic missile spell. When cast, the spell brings into being a small set of pointed teeth that are fired outward from the caster's body. One set of teeth is created for every two levels of experience beyond the 1st possessed by the caster (e.g., a 3rd-level caster would create two sets of teeth) to maximum of four sets of teeth. The teeth strike as 5-HD monsters; any creature struck by a set of teeth must save vs. spells or be slowed for 1-4 rounds. The caster can divide the sets of teeth among as many opponents as he desires so long as they are all within a 10' square selected as the focus for the spell. Hits from multiple sets of teeth require multiple saves, unless a save is failed and the victim is slowed. Further bites from the same casting of this spell have no effect once the victim has already been slowed.
Spider gout (Conjuration)
- Level: 2
- Components: V,S,M
- Range: 10 yds.
- CT: 2
- Duration: Instant.
- Save: ½
- Area of Effect: One creature
This spell creates a magical glob of spider venom in the caster's mouth, which the caster spits out at any single target within range. The caster may retain the venom for a number of rounds equal to half his level. If he retains it longer, he suffers the damage detailed below, without any saving throw. The caster can spit the venom up to 10 yards, whether he normally is capable of such an action or not. The caster must make a successful attack roll to strike the target (no range penalties apply). Failure indicates the venom glob missed, causing it to dissolve harmlessly. Creatures struck must save vs. poison or suffer 2d4 hp damage plus 1 hp per level of the caster to a maximum of +10 hp damage at 10th level. A successful save indicates only half damage. The material component is the neogi's own poisonous saliva.
- Level: 3
- Components: V,S
- Range: 5 yds./level
- CT: 3
- Duration: 1 rd./level
- Save: Neg.
- Area of Effect: Special
Upon casting this spell, the caster creates the illusion of thousands upon thousands of crawling spiders. Only a number of creatures equal to the level of the caster can be affected by this illusion, and all must be within a 10'-diameter sphere. Any creature targeted by the spell must save vs. spells, success indicating that the spell has no effect. Any creature who fails its initial save must save vs. spells again. Success now indicates the creature flees from the area at its fastest possible movement rate for 2-5 rounds. Those who fail are so frightened that they are unable to do anything except try to remove the spiders they believe are crawling all over their bodies.
The illusion this spell creates is different for each individual. It might be argued that, for example, umber hulks have little to fear from spiders. But when those spiders are 1' in diameter with armor-piercing fangs, there is much to fear. The neogi tend to use this spell to disrupt and disorganize enemy forces when boarding actions are taking place.
Note: Regarding the initial saving throw, DMs must decide whether the target creature has reason to believe that what he is witnessing is an illusion. It is not unreasonable to assign a beneficial modifier to the initial save roll if the target has reason not to believe in the illusory spiders.
Identify race (Divination)
- Level: 4
- Components: V,S
- Range: Touch
- CT: 4
- Duration: 1 rd./level
- Save: None
- Area of Effect: One creature
This unusual spell is used by the neogi to identify the capabilities of a newly encountered race. The spell provides for the caster the name of the race (as it is known to the creature itself), its general combat abilities, a brief knowledge of the creature's customs, and what the creature needs to survive. The spell can identify only one piece of information (e.g., the usual methods of attack) per round. The DM must decide if the information being sought is available. The spell will only identify with that particular creature's life, not the race as a whole, so different readings are possible. For example, the lifestyle and abilities of a human wizard of Thay from the FORGOTTEN REALMS® setting will differ greatly from those of a human Knight of Solamnia from Krynn of the DRAGONLANCE® saga.
This spell is used by the neogi to determine the abilities and needs of a potential slave without serious risk to the slave's life. Although this spell may seem somewhat trivial to other races, it has been witnessed that ships bearing neogi wizards capable of casting this spell have far more powerful slaves than those that do not.
Lethal hatchling (Necromancy)
- Level: 5
- Components: V,S
- Range: 10 yds
- CT: One round
- Duration: Special
- Save: Special
- Area of Effect: One creature
Upon utterance of this spell, the caster conjures up a small, 1 -diameter egg that fires outward from the caster and toward the target. The target is then entitled to a save vs. death magic. If the save succeeds, the spell has no effect. Failure indicates a most gruesome fate: The egg enters the victim's body and begins to grow. For the next four rounds, the target is entitled to another save vs. death magic each round at a -2 cumulative penalty (i.e., -2 on the first save after the egg enters the body, -4 on the second, etc.). Each failed save results in a loss of 25% of the target's original hit-point total. If the target makes a successful save during this time, the spell is halted and the egg's growth stops and then deteriorates. If the target dies, a newborn neogi erupts out of its body.
Some neogi wizards have been known to cast this spell to replace neogi lost in earlier combats. This is a rare occurrence, however, as it usually requires the sacrifice of a slave to do so.
Charm of distraction This minor magical item is usually shaped as a pendant in the form of a neogi's head looped through a chain. The wearer of this magical item gains several benefits. First, the charm acts as a standard ring of protection +1. The charm also bestows upon the wearer an additional +1 (for a total of +2) on saves vs. enchantment/charm spells. Lastly, the charm provides the function of magically holding an opponent for one round. This can be done once per day and is otherwise similar to the wizard's hold person spell, cast at the 8th level of ability. The neogi can attempt this hold on any single target he can physically see. The target of the hold is entitled to a save vs. spells. If successful, the target is unaffected. If the save is failed, the target is unable to take any actions until the following round. The neogi are very fond of this item, as it often buys them an extra moment to escape from the clutches of an enemy or distract the foe long enough for the neogi's umber hulks to rip them apart. XP Value: Nil (cannot be made by PCs)
Bands of the serpent Only neogi possessing magical ability can make use of this item. These metal bands, always found in pairs, are worn around the spiderlike legs of the neogi and bestow upon the wearer the following abilities:
- The wearer of the bands receives a +1 bonus on all saves vs. poison. This bonus is cumulative with other forms of protection.
- The wearer can communicate with any form of reptile through a limited form of telepathy. This includes lizard men and other sentient reptiles as well as the mundane forms. This telepathy does not give the neogi any ability to control reptiles, however.
- The wearer can transform himself into a giant poisonous snake. The wearer gains all of the abilities listed in the Monstrous Compendium under Snake: poison, giant. The wearer retains his own hitpoint total. The wearer can transform into snake form once per day, each change taking one round to complete and lasting up to six turns.
This item neither has nor requires charges. Neogi who possess these rare items will go to great lengths to keep them out of the hands of other neogi as well as adventuring parties. XP Value: Nil (cannot be made by PCs)
Bands of the arachnid These bands are always found in pairs and are very similar in appearance to the bands of the serpent. The bands are worn around the spiderlike legs of the neogi. Only those of that race who possess magical ability can make use of them. The wearer gains the following abilities:
- The wearer receives a +2 bonus on all saving throws vs. poison. This is cumulative with other forms of magical protection.
- The wearer is immune to the effects of any spell or spell-like ability that affects movement (e.g., slow, hold, etc.). This power is always in effect, regardless of the wishes of the wearer. A side effect of this ability is that the wearer can move freely through any web, magical or otherwise, as if he were an actual spider.
- The wearer can transform himself into a giant spider. The wearer gains all of the abilities listed in the Monstrous Compendium under Spider, giant. The wearer retains his own hit-point total. This transformation lasts a number of turns equal to the wearer's experience level. The wearer can transform into spider form once per day.
These items neither have nor require any charges. Neogi who possess these rare items will go to great lengths to keep them. Neogi cannot wear more than one type of magical bands at any time. XP Value: Nil (cannot be made by PCs)
They mostly got ignored once Spelljammer died, but Lords of Madness in 3e had a whole chapter on them with a mini-adventure, and they had both an appearance in the Monster Manual 2 and an Ecology article in Dragon Magazine in 4e. In 5e they were officially added back into the game with Volo's Guide to Monsters, which statted them out, described their life-cycle (though they now lay their eggs on the Great Old Master rather than just having him suddenly die of pregnancy), and softened them just enough that they can now cooperate with other civilizations as evil and depraved as they are in situations where self-preservation overrides their natural desire to enslave and dominate. This makes them a bit less "enslave at all costs!" and more greed-driven space-slave-merchants.