Derro

Crazy, evil midgets from the depths of the earth!

The Derro are a race of insane and evil dwarf-like (better: morlock-like) humanoids that inhabit the Underdark in various Dungeons & Dragons settings. They differ from the similar Duergar and even morlocks in that they are even more neurotic and malevolent in nature.

Gary Gygax brought them into the Advanced Dungeons & Dragons 1e module take on "S4: The Lost Caverns of Tsojcanth", which entry the Monster Manual II basically reprinted. They were updated to 2nd edition in the Greyhawk modules "Greyhawk Ruins" and "Flames of the Falcon"; and, subsequently, From the Ashes and the Monstrous Manual. Dungeon Magazine #81 introduced a variety of derro mutants, including multiple-armed ones, derros with eyestalks, and derros conjoined with grimlocks. The baseline derro went on to 3e's Monster Manual. 4e held off until Monster Manual 3; 5e put 'em in adventure Out of the Abyss.

Derro were based upon the Dero, a race of sunlight-averse, psychic, sadistic, degenerate aliens that the legendarily insane pulp sci-fi writer Richard Sharpe Shaver asserted were secretly in control of the world. You will note then that this means that they do not fit under the Open game license the way other creatures are so you will see Derro popping up in other media.

Derros are considered fucking hilarious in England's own Underdark, Australia, because 'Derro' is another word for "Bogan cunt" or “deadbeat” (from “derelict”) down t/here. (Bogan being the far more manly and badass equivalent of a Hoodlum or Chav, or Australia's equivalent to Rednecks)

Greyhawk

Derro attacking the party in module S4

As the Lost Caverns of Tsojcanth took place in the Greyhawk setting, and as Greyhawk-sans-serial-numbers was basically the default setting of 3e, one can consider the Oerthian Derro to be the "standard" derro for the first three editions of the game.

Derro are small, dwarf-like humanoids, standing around 4ft tall, with skin "the color of an iced-over lake" (white with bluish undertones), hair that is sickly pale yellow or tan, and creepy staring white eyes that lack visible pupils. Their features have certain traits of both humans and dwarves; in the 1993 Monstrous Manual, it's explicitly noted that they remind dwarves of humans and humans of dwarves, whilst Dragon Magazine #241 would finally expand upon what that entails. The physical stature of a derro is predominantly human, but with short, thick limbs and dexterous fingers, more like a dwarf. The head is somewhat disproportionate, seemingly oversized, with high foreheads, thick and hairless brows, and receding hairlines being common. A derro's face has a small and hairless chin (although males do grow moustaches, and often wear them long and thick), protruding cheekbones, small round ears, and distinctively egg-like eyes that are solid white in color.

The Monstrous Manual also describes them using human slaves as breeding stock. In issue #241 of Dragon Magazine, it's finally explicitly stated that derro are the degenerate descendants of forced human/dwarf interbreeding, a project enacted by the Suel Imperium to create a superior strain of slave laborers. Weirdly, this same issue claims that derros mating with dwarves produce only sterile male derro of superior strength.

It... didn't work out well. Whilst the wrath of the angered gods Fortubo (who saw the use of the "dwur-rohoi" as a blasphemy of his principles), Moradin and Berronar Truesilver was certainly terrible, the truth of the matter is that derro spent generations as the Imperium's slaves, until it was destroyed in the Rain of Colorless Fire; thanks to their being hidden in deep subterranean mines, the derro survived this cataclysm, and indeed see it as a divine blessing that set their race free.

In AD&D, the derro are defined mostly by being evil; having been slaves their whole existence, their culture now revolves around their burning desire to attain power and vengeance, which to them is synonymous with the ability to inflict as much suffering, degradation and sorrow upon denizens of the surface as possible. They are ruthless, sadistic, abusive and violent, with a certain racial propensity towards aimless paranoia and mob mentalities. Their first great racial drive is to enslave, torture and murder their enemies, which is most everybody who isn't a derro, but especially surface races and humans in particular. Their second great racial drive is the pursuit of magical knowledge; unlike dwarves, they couldn't care less for gold, but magic? That's valuable to them - which may stem from their Suloise ancestry, or at least so surmises Dragon #241.

Such is their hatred of other races that derro regularly declare "Uniting Wars", which are massive, pointless conflicts in which derro rise up en-masse throughout the Underdark and attack everything around them that isn't another derro, battling until their numbers have been reduced to the point they have to give it up and go back to survival. The savants don't believe these Uniting Wars will ever actually succeed, but they purge the weakest of their numbers and terrorize other races, and that's good enough justification to declare them, as far as they're concerned.

In 3rd edition, though, derro went from just being strongly inclined towards evil (like the duergar and the drow) and gained the trait of being absolutely batshit crazy as a race as well, with mental illness running rampant throughout their species. According to 3e's Monster Manual, this madness most commonly manifests as a combination of delusions of grandeur, sadism, and murderous impulses that they struggle to control.

Regardless of edition, derro live in violent tribal groups, which bow to the whims of the strongest derro present or else to the savants; derro sorcerer-clerics who wield potent magical abilities. Their loyalty to their savants is absolute; derro revert to fawning and cringing like abused slaves around those stronger than them anyway, but will leap to obey the most suicidal order a savant may give without the slightest hesitation. When fighting, they favor the use of daggers, light repeater-crossbows (usually stocked with poisoned quarrels), spiked bucklers, and a hooked shortspear that they use to drag victims from their feet.

The savants draw their power from a minor deity called Diirinka, who is said to have ascended to deity-hood by stealing magical lore from Ilsensine and abandoning his twin brother Diinkarazan to the illithid-god's wrath. He is an uncaring god, and so long as they preach for the derro to fear and respect him, he lets them have free reign in their lives.

Derro are even more strongly allergic to sunlight than their drow and duergar neighbors; sunlight physically hurts them, burning their tainted flesh, and will actually kill them with prolonged exposure. Ironically, their ability to see in the dark is surprisingly poor; a mere 30ft Infravision in AD&D (which was misprinted as 3ft in the Mosntrous Manual!) and no darkvision at all in 3rd edition - instead, they compensate through their keen sense of hearing, which gives them the ability of Blind-Fighting in either edition.

Forgotten Realms

Izhkin, a derro character from the Storm Coast Legends video game. Rather scrawny.

As with most things, the Faerunian take on the Derro is pretty much the "generic" Derro fluff with some setting-unique names to their places of residence. At least, this was the case until the 5e update, seeing as how 5th edition basically uses the Realms as the "default" setting.

These new, uniquely Faerunian derro are stated to be a dwarf offshoot species, once enslaved by the Illithids before they managed to violently free themselves from the yoke of their captors, but not before the gruesome experiments and exposure to the brain-twisting psionics of their masters had left the race's collective psyche scarred, and afflicted them with incurable madness. Every single derro is insane in some fashion, and this has made the race into one of second-class citizens; stripped of the ability to function in large groups without savants or other charismatic figures to rally behind, they don't establish their own settlements and instead either infest the cities of other Underdark races like vermin, or are kept as slaves by the greater powers of the Underdark - the drow and the duergar. "Mordenkainen's Tome of Foes" makes it explicit that derro were once part of the duergar dwarf clan, but responded particularly badly to the illithid experiments, such that when Laduguer freed his people, he abandoned them as beyond saving.

As with the Oerthian derro, those of Faerun also fight their Uniting Wars, but these serve predominantly to manage their population; unlike dwarves, derro are quite a fecund race, maturing and breeding with considerable speed, although it's unclear if this means closer to human or closer to goblin.

In pre-5e lore, Diirinka and Diinkarazan were said to be outcast kin of the Morndinsamman. In 5e lore, it's mentioned that the derro still worship these two brother-gods, but they are not believed to be real deities by the scholars of other races.

Dragonlance

Theiwar

On the world of Krynn, whilst the derro proper are absent, two of the Mountain Dwarf clans embody different aspects of the Derro family tree, although it's noted in Dragon #241 that these are not "true" derro, which migrated from their birthworld of Oerth to other worlds in the multiverse.

The Theiwar are based upon the Derro Savants; hideously ugly creatures, with huge bulging eyes of gray or watery blue color, pale tan or yellow hair, and bone-white skin with bluish undertones. Uniquely amongst the mountain dwarves (at least in AD&D), theiwar have an affinity for magic, which allows them to not only take levels in the Cleric class, but also grants them spell-like abilities.

The Klar are based upon the "common" Derro; often forgotten from the list of dwarves native to Krynn, Klar are noted for their large eyes, their aversion to sunlight, and their rampant racial propensity towards insanity.

Nentir Vale

4e Derro

In the Nentir Vale, derro are explicitly not dwarves, but rather are the stunted, degenerate descendants of a mad human empire that attempted to draw power from the Far Realm. Needless to say, this was a fucking terrible idea, and they were so dangerous that the Primal Spirit known as the World Serpent reacted by dragging the entire proto-derro empire from the surface of the planet and imprisoning them in the depths of the Underdark.

Locked away in the dark, trapped with their Far Realm rifts, the derro devolved into stunted, crazy horrors. In fact, they're known for being so absolutely batshit insane that even Drow find them horrifying and have a "kill on sight!" order about the whole race! Absolutely nothing humanoid will voluntarily work alongside a derro, and they exult in that fact. Rampantly insane, still in-thrall to Far Realm worshipping witch-priests called Savants, the derro pursue a life of deranged violence and suffering, seeking to enslave, kill, devour and experiment upon everything else with the vague ultimate goal of unleashing their aberration masters upon the world.

Pathfinder

When Pathfinder learned they could get away with bringing derros into their own game, they decided the best way to do it was to try and more explicitly use the themes of the original Dero stories, which is expanded upon in the sourcebook "Classic Horrors Revisted".

Derro on Golarion are actually corrupted fey, descendants of the same root-stock as the Pech, but diverged from them centuries ago when they fled a civil war amongst their race that brought them towards the surface. A combination of starvation, struggle and addiction to the one source of nourishment they managed to find, the brain-altering and toxic fungus cytillesh, caused them to mutate into their current forms, whilst also afflicting them with racial insanity and wide-spread infertility.

This keeps the derro a fairly rare race, and this is a mercy; obsessed with understanding why the residents of the "Overburn" are not affected by the sun's rays in the way that they are, the derro conduct a ceaseless campaign of experimentation, performing all manner of insane and unholy regimes of gaslighting, dissection, vivisection, grafting and other forms of fleshcrafting - worse, because of their insanity, derro do not pass on the fruits of their labors, meaning that the race's goal is impossible to achieve, as each generation dismisses the works of its predecessors and starts over from scratch. They conduct endless nocturnal raids on the cities under which they establish their lairs, covering up their depredations with crude brainwashing (surgical, psionics, or both) and assassination. Vicious cannibals, the only races they typically interact with are morlocks and mongrelfolk, whose flesh they regard as inedible.

Eberron

Derro is relatively new in Eberron, only first seen about 400 years before the "current days" of 998 YK. Because around the same time dwarven clan Noldur mysteriously disappeared a lot of people think derro are mutated and twisted descendants of the lost clan, although whether it's true or not remains an open question. Nomadic derro tribes wander through the depth of Khyber, mysteriously ignored by most of the aberrations and monsters living there and ignoring them in return. Eberron derro magic tends to be more druidic than sorcerous, with heavy Lovecraftian undertones and fleshcraft body-horror vibe to it, replacing vines and plant growth of usual druidic spells with tentacles and blobs of flesh growing out of the walls. As the dwarves of Mror delved deeper into the Realm Below and get into ongoing war with aberrations serving Dyrrn, derro tribes kinda joined the war on Dyrrn's side, not really coordinating with the legions of Dol and other monsters, but still attacking dwarves at every opportunity they get. As the combination of flesh-shaping magic and insanity all but screams "daelkyr corruption", the most popular theory is that they were twisted by Dyrrn into their current form.

Derro PCs?

Stats for playing a derro appeared under the Advanced Dungeons & Dragons ruleset in issue #241 of Dragon Magazine, in the article "Legacies of the Suel Imperium". 3rd edition technically also features playable derro in the Monster Manual, but it's one of those races where the DM is left to reverse-engineer it from the statblock.

For the 2e statblock...

Ability Score Minimum/Maximum: Strength 3/17, Dexterity 12/19, Constitution 3/18, Intelligence 9/19, Wisdom 3/17, Charisma 3/18

Ability Score Adjustments: +1 Dexterity, +1 Intelligence, -1 Strength, -1 Wisdom

Class & Level Limits: Fighter 10, Wizard 12 (13 if Specialist), Thief 15

Multi-class Options: Fighter/Mage, Fighter/Thief, Thief/Mage

Thieving Skill Racial Adjustments: Pick Pockets +5%, Open Locks +5%, Hide in Shadows -5%, Detect Noise +30%, Climb Walls -10%, Read Languages -15%

Hit Dice: By Class

Natural Armor Class: 10

Movement Base: 9

Infravision 30 feet

Free Blind-Fighting Proficiency

Magic Resistance 30%; this applies against beneficial spells and magic items as well as against spells cast on the derro doesn't prevent a derro mage from casting spells.

Mage-Savant: A derro wizard can Comprehend Languages and Read Magic at-will.

Stonecunning: As per the Dwarf ability.

Sunlight Allergy: Derro suffer a -2 penalty to all c ombat rolls, defensive adjustments and saving throws whilst exposed to sunlight or to magic that duplicates prolonged sunlight. They also suffer 1 hit point of damage per hour exposed to sunlight, of which only 1 hit point will heal naturally per day.

Bad Reputation: The legendary reputation of derro as sadistic, torturing, slavers from below means that a derro's Charisma is capped at 8 when interacting with non-Derro.

Religious Enemy: Human, dwarven and gnomish priests of Fortubu will attack derro on sight.

Mandatory Weapon Proficiency: Dagger.

Unstable Psions: A derro may have wild talents, but cannot take the psionicist class.

Monstergirls

You're her most precious experiment...

Surely, you're thinking, the derro can't have received the monstergirls treatment? Well, you'd be...somewhat disappointed. The idea of sexy derro-girls is uncommon, to say the least, but it does exist, and mostly because of that one entry in the Pathfinder Inner Sea Monster Codex, combined with Pathfinder making female derro look surprisingly fappable.

So, if you're okay with crazy shortstacks whose flaws can range from mere delusions of grandeur through sadism and into yandere, derro just might be for you.

Gallery

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  S4
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  A derro savant from module S4.
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  The derro contrasted against its kinsfolk, the duergar. Can you pick which is which?
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  3e
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  5e
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  5e
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  PF
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  PF
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  PF
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  PF
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  Midgard

Further Reading

The Derropedia, the blog of some guy who is absolutely obsessed with Derro. Last entry was 26 September 2020.