diegetic monster statblocks (with attached generator)

A good statblock is glanceable, allowing the GM to quickly get the information she needs. Here's a shot at what that might look like for FKR-style or systemless treatments - though it's kind of a rough draft and I expect others will be able to iterate and improve. Very stupid monster generator attached!

necromancy, exorcism & undead

*places flashlight under chin* oOoOoOoh it's a Mosaic Strict-compatible system for calling and turning undead!

  

Every dead person has a SPOOKINESS rating, and every context has a SANCTITY rating. When spookiness equals sanctity, you can perceive the dead out of the corner of your eye. When spookiness exceeds sanctity, the dead walk, hover, shamble, and creep upon the earth! If a dead person doesn't have its own corpse to use, it might well manifest outside of it, or inside a person. The more that spookiness exceeds sanctity, the more powers the dead manifest.

Spookiness

Default Spookiness is 0. Add one for each of:

• the deceased knew necromantic rituals (see below)
  
• the deceased had ever performed a necromantic ritual
  
• the deceased was a kinslayer, or slain by kin
  
• the deceased died by torture, suicide, or something else particularly tragic
• the deceased had eaten the flesh of sentient beings
• the deceased has unfinished business (either something they deeply care about, or an unfulfilled oath, whether nor not they care about it)
• the deceased would have very strong opinions (in any direction, but strong enough to make it a prospect of daily reflection) about the prospect of showing up as undead
  

Decrease by one for each of:

• the deceased has been properly buried
• the living kin (by blood or by ceremony) of the deceased have honored them within the last year

Or assign spookiness according to GM fiat.

Regularly offering alcohol and sweets to the dead can decrease or increase spookiness, depending on whether you request their presence or slumber. Offer them every night for a week to shift by one, or once a night for a year and a night to shift spookiness by two.

Necromantic rituals exist that can shift spookiness up. These are jealously guarded and dangerous to use, even beyond the danger inherent in increased spookiness. Here are a few:

The Truthful Turret

Dig up the bones of someone who has been properly buried for over a century, and arrange them in a sort of small tower which contains something they have written, but which no one else (including you) has read. Burn it. Increment spookiness of the smoke rising up by 1d6-1.

Voice of the Tunnel

Cut out your own tongue, and place it in the mouth of a corpse that has been properly buried, returning it to its proper place. It gets +1d6-1 spookiness as long as your tongue is there and it remains in its burial spot, and can communicate when you sing out of your tongueless mouth. (The relevant sanctity rating inhibiting this is the one where you are.)

The Stallion Path

Sprinkle the warm blood of a saint, monarch, or unicorn over the dead. (If the being whose blood it is is still alive, they can't consciously approve, unless they're you.) They all get +1d6-1 spookiness. They're bound to obey the being with the highest spookiness or spookiness-conditional-on-death around, though they'll also hate that being and tear them to shreds if they ever get a chance.

The Caul-Sister

Dress up a corpse to look just like you. Then, make sure that no one uses your true name to refer to anything but the corpse. Keep it that way for at least a year and a night.

When you die, your consciousness is transferred to the corpse and you/it combine spookiness levels. Add on an extra one if it is your actual identical twin.

Sanctity

Default sanctity is 8 in sunlight and 4 otherwise. Add one sanctity for each of:

• this is a literal sanctified place
• the largest community within one night's walk has had a feast since the last midnight celebrating life and honoring the dead, and not containing any violence except (1) animals slaughtered according to humane religious procedures (2) small convival brawls
• if it's been a year and a day since something truly awful has happened here (where the boundaries of “here” are determined by lines of salt, stone walls, village boundary markers, bodies of running water, and/or one night’s walk, whatever is most restrictive) but living people have (+2 for a decade and a day, +3 for a century and a day, +4 for a millennium and a day)
•  it's a full moon
  

Subtract one sanctity for each of:

• this was a literally sanctified place, but has been desecrated
• if it's been a year and a night since sunlight or living beings have been here (-2 for a decade and a night, -3 for a century and a night, -4 for a millennium and a night)
• it's the new moon or an eclipse
• just now, someone says something blasphemous without being contradicted
• all living people present are drunk or in panic
  

Or assign sanctity according to GM fiat. 

Exorcism and Turing Undead

If you speak in a strong voice and command the dead to return to their slumber, and no one else has attempted the same thing in the same scene, you can increase sanctity. Roll 2d6 and ignore any pip face greater than your SACRAMENTAL POWER ranking. Sacramental power starts at 0 and increments by one for each of:

• You have never killed anyone by your own hand.
• You have kept an inconvenient oath for a year and a day.
  
• You are wearing the (useless, armor-wise) vestments of office of an ordained priesthood. (You don't actually have to be ordained, ghosts are dumb so vestis virum facit for this purpose.)
• You have tried and failed to turn undead before and experienced either permanent wounds or the death of a comrade.
• You have succeeded at turning undead of this spookiness level before.
• You know the Seventeen Names of God.
  

Unicorns: the astonishing science behind the myth

MYTH: Unicorns bless and adore virgins.

FACT: This superstition has a considerable basis  in truth; unicorns scorn the married as they scorn parents, and are most often found by those in the flower of young adulthood. But a unicorn may grace avowed sluts, as they disdain those who have taken holy vows. Those who have been "married" according to the fiction of local law but without their consent may find a unicorn, but not every thing that may repel the unicorn is freely chosen: no man or woman in line to inherit a throne, despite what the stories may tell you, has ever seen a unicorn, except perhaps from a great distance, carrying some other hero.

Unicorns are creatures of most awesome and terrible Law, bearers of Obligation, and will not subject anyone with currently standing obligations to the fulsome grace of their presence. 

MYTH: Unicorns never charge someone with a task that is beyond them. Relatedly: those chosen by unicorns are special, virtuous, talented people, a class apart. Relatedly: those tasks assigned by unicorns are special, virtuous, necessary.

FACT: Unicorns frequently oblige persons to quests which are nonsensical, amoral, or simply catastrophic. An untalented young artist is as likely to be charged by a unicorn with writing the Great National Epic as a talented one; good governments as well as bad are assigned to be overthrown; unicorns may appear to unattached persons and charge them with installing terrible tyrannies. Two persons who have seen the same unicorn may be sent on logically incompatible quests.

The extent to which a unicorn chooses either the victims or their new obligations is unknown. While meeting the unicorn and taking on their task is greeted with delight by some, and feels as though voluntarily taken on, it is known that many others despair of their new obligations.

MYTH: The unicorn is a mythical elaboration of a real creature, the monoceros of distant lands.

TRUTH: Many mythical creatures, such as the rhinoceros, the triceratops, the ki-in, and the dryad, fatal to be seen in her nakedness, are garbled second-hand versions of that very real creature, the unicorn. The morphological diversity of these creatures underscores that the unicorn may not look just like what one expects. One may be in your peripheral vision right now - but you will not notice it, unless the conditions are right.

MYTH: Unicorns are the sworn enemies of Night-Mares, and will do battle with them.

TRUTH: The night-mare is but the unicorn driven to insistency. Against an obstinate acquaintance who dallies or refuses her quest, a unicorn visits in sleep to offer unwelcome encouragement in the form of restless dreams and mornings of unwished memories. These tend to get worse over time.

It is true that some black-guards have been known to ride night-mares into battle. Some people react to the night-mare's tortures by inuring themselves rather than complying, and by overcoming their fear of the enraged unicorn, they may tame it and ride it into battle. To so harden oneself is a rare feat, however.

MYTH: A unicorn's presence and unwished charges can be banished by losing one's virginity. Related myth amongst those disabused of Myth #1: the unicorn, and in particular its manifestation as the night-mare, can be thrown off by taking on new obligations - marrying, being elected to office, or perhaps even a simple vulgar oath.

TRUTH: Few myths cause quite as much disaster as this. Far from hemming in the unicorn, taking such oaths permits the jealous night-mare to visit its horrors upon those to whom the oath-taker has attempted to oblige herself.

MYTH: The unicorn is beauty and grace.

FACT: As anyone who has met a unicorn can attest, some myths are true.

(1d20 rumors about the) Medusa Men

1.  That the less fair sex among the medusa race (which must surely exist, as a posit of the doctors of comparative physiognomy) tend towards natural reclusiveness on account of their unlovely appearance. 
2. That the female medusas, famed for their dangerous beauty, are likewise repulsed by this.
3. That it is thus explained all the stories told by besotted adventurers at inns, that they blindfolded made love to the poison-gazed women, and felt the snakes snapping at the sweat on their necks.
4. That the above is romantic bluster, and that there is a more parsimonious explanation to be found for the misshapen creatures known to bow and scrape before the stone queens. That for every man or beast or tree so petrified, so an equivalent amount of shale or dirt or coal is carnated.
5. That the souls of such victims are encased in the misshapen medusa-men.
6. That to save someone from petrification, their stony counter must be annihilated.
7. That to save someone from petrification, their stony counter must be rescued from medusal servitude, treated well, nurtured, until it grows into the original.
8. That the misshapen medusa-men do not bear the souls of the petrified, but are travelers from another world.
9. That the medusal world is a reverse of our own, as the stony counters are mockeries of petrified victims; that it is a world of present absences and absent presences. That there planetary pockets of air rotate and revolve through an infinite expanse of meat, and that on the inner surface of these pockets mineral men plow fields of blood in hopes of growing edible stalagmites, and ply shale boats over snake-cilia seas.
10. That the medusa herself comes from this world as well. That she does not avert her gaze from mirrors for fear of an end, for in fact she longs to return home, but out of duty. A medusa who is determined by a star chamber of stone serpents to have allowed herself to return voluntarily is punished, forced to remain in the grotesque form of muscle and bone forever, whereas if it is determined to be an accident, she may be promoted from iron to crystal and enjoy a retirement on a country estate. That they, homesick, subconsciously look for ways to be “accidentally” “defeated” in this wise.
11. That the petrified are not deceased, but only parted; for they sojourn in the medusal world. That the only way to “save” them is to wait to let them finish their business there, trundling on granite legs across an epidermal plane, and rap their obsidian knuckles on the cartilage door of the House of Passage.
12. That many sages have wandered into the bowels of the earth to be seen by the medusa and wrest secrets from her world, only for her to lean in, eyes closed, and offer them a welcome embrace, as if she knew and endorsed their purpose, and bit their neck hundreds of times in a second with her hair. That her hair’s venom offers visions of such a world, but that it is false.
13. That through the petrified body of such a one making a sojourn, one may not communicate, but through a statue of their likeness, one may, though the other world may peer through it as well. That this was the origins of idolatry in a society whose lone religion before was the vision quests of its thinking class into the stone-as-flesh world, and their medusa tutors, who were our patrons once but have turned to other projects in our maturity.
14. That to gaze into the eyes of a medusa-man, whatever its origins, is to return it to stone. That this creates an equivalent amount of flesh from nearby stone and that thus a single medusa-being (perhaps the double of a mouse) is very useful to a sculptor or architect, for it may be repeated for as many occasions as result in something with eyes. That the only reason this is not more widely known and used is the trade secrets of masons, which will make them a great power in latter days, and the rareness of medusas.
15. That the only reason repeatedly petrifying and awakening and petrifying one’s one little flock of medusa-men or -mice or -mites is not more widely known and used is that it is a terrible idea, a swift form of ocular toxification. That little nodules of gypsum flower within one’s stomach and brain with each locked gaze, and that many a delapidated alchemist’s tower may be found with strewn with lumpy architectural experiments, feral homunculi, and the calcite corpse of an alchemist.
16. That the stones which look to be in the likeness of bone beneath the earth or on cliff surfaces are not the long-weathered bones of dead species, as the superstitious surmise, but the premonitions of ones to come. That geology in her wisdom has crafted them to be awoken by the Medusa’s in breeding pairs, when their gaze extinguished those whose place they will take.
17. That medusas thus listen with seismograph, bite themselves with their hair, and blast with dynamite into deeper caverns still to ascertain the divine will of geology, for they are the midwives and executioners of her will. That they under heavy hoods walk into taverns and ask stout-hearted women and men to undertake some task of doom to recover a certain stone or plumb a certain depth, that they may hence know what species or people is to be ended, and which to begin.
18. That medusa-men are not always so ugly. That sometimes their shapes come out quite human, and their “memories” too. That this is why some of those stout-hearted folk in taverns long to traverse deep beneath the earth, though they cannot explain why.
19. That if such a one meets a medusa’s gaze, he will not turn to stone, but to god, higher version of himself, or medusa.
20. That the male sex of the medusa race does indeed exist, and that if they had bodies, they would be quite beautiful. That they are charged with the petrification and carnification of not species but ideas, and that for the sake of mercy they remain in slumber or meditation, turning their conceptual gaze towards nothing. That various improvements and innumerable apocalypses could be won by whispering the right words in their nonexistent ears, tempting them towards the destructive act of particular consideration.

d20×4(ish) intelligent lifeforms

Partially inspired by Skerples' post.

Wayne Barlow

d00Z3 oobulous oozes

delightful demons and angels of awful purpose

Outsiders in D&D are connected to alignment system, but the alignment system has always been ambiguous about whether it refers to psychology or behavior. This opens the room for outsiders whose psychology conforms to the core concept, but with behavior that isn't necessarily expected.

Evil angels are the easiest one, because you've seen them all before. Angels do whatever God asks of them, because God is good. God is indeed the fullness of being, and most of reality is contained within the godhead; all creatures are just a sort of ephemeral leftover. But it must be emphasized that even the angel who commits terrible atrocities, pouring out their philters of doom over Sodom or Jericho, weeps genuinely as they do so. How tragic, that the greatest good should require such! Like an abusive parent, they say "this hurts me more than you," and they are right. They are genuinely eager to avoid as much wrong as can be managed, and will be thankful to anyone who can point out creative solutions to the dilemmas ahead of them.

1d4 Angels of Awful Purpose

1. He announces himself to prophets, holy men, and other worthies, and reveals the Divine Plan; these plans are lies, the prophecies false, that the face of the God might remain hidden, and faith remain faith. He smuggles in worthy moral teachings and the like when possible.
2. She is tasked with ending intelligent life on this plane and has been spending the last few centuries disseminating information on birth control, celibacy, and the like. Her archangelic superior is coming, bearing a heavy heart and the news that the timetable must be moved forward.
3. They tempt men and women with lust, money, and power, that their souls might be tempered, and that the halls of heaven may remain unpolluted. They may every attempt possible to choose those who will be tempted enough for it to be a difficult decision that forces them to bend, but not be broken. But sometimes they miscallibrate.
   
4. It seethes with hatred for all life, for all justice, and for all goodness. It does this because there is another angel - its dear friend, in fact - who has been assigned the awful task of torturing the most wicked soul available, and it therefore needs a way to be wicked (and thus spare others) without hurting anyone.  It plays a dangerous game of doublethink, for its wicked thoughts must be intense without being genuine enough to inspire it to truly act on them. Looking at the increasing evil of men, it binds itself in chains that it might go deeper into depravity and yet not become harmful, but no chain lasts as long as intended.
   

Devils are conniving bootlickers, looking for the best bargain for themselves and holding to it assiduously; they are nothing if not consummate game theorists. Good devils have read Kant and know that, if you're like most beings (and most beings are), choosing to cooperate means that most beings are willing to cooperate. Like angels, "good" devils are smug about their goodness, but they're smug about it because they think they've found a particularly effective trick in the nature of decision theory, and are pleased to have exploited this loophole in the nature of reality. It must be emphasized that even "good" devils don't give a rat's ass about anything that happens to anyone else; indeed, they generally find others' suffering as funny as the normal kind of devil. It's just that they'll alleviate it, given the chance, and grumble about it too.

Chaotic devils have recognized the antagonistic rather than cooperative nature of reality, and that mixed and random strategies are often the right way to deal with an opponent, especially the omnipresent opponent of "everyone who isn't me." "Chaotic" devils employ these mixed strategies every bit as methodically as any other kind of devil; they forgo pleasurable opportunities, think about the long term, keep records of their behavior to spot and correct the existence of observable patterns.

1d4 disconcerting devils

1. He is the Prince of Darkness, the classical Satan. When he first came into being he resolved he would cooperate with God if God cooperated with him, and (to maximize the chance of being cooperated with) to retaliate at any cost to himself if God did not cooperate. God then commanded him to do something other than what he really wanted, so he's at war with an omnipotent being. God works in mysterious ways, doesn't he? Anything you do can and will be turned against you. He tries to sow as much chaos as possible to interfere with the divine's plans; currently, he considers that doing good (or what would immediately seem to a mortal like good) mostly results in this moreso than evil.
   
2. She rides with an order of paladins, righting wrongs and working justice. To let off steam she tortures animals and defiles corpses, since animals and corpses can't rationally commit to any decision theory so you don't need to include them in your Kantian calculations.
   
3. It had a great gig torturing sinners in the depths below - eternal torture of sinners is good altruistic game theory after all, it's committment to a tit-for-tat equilibrium of the grim trigger type. And its fun! Now it's on earth for some reason and doing the rational thing isn't fun anymore. It can deal with this but doesn't like it.
   
4. They cut a deal with a good god, and a deal's a deal.
   

Demons always do whatever they feel like, without any regard for their own or anyone else's interests. "Good" demons feel like helping people, and "lawful" ones feel like obeying particular rules or particular persons, but these are fundamentally whimsies and compulsions, not values or commitments. Some people believe that faeries are actually misclassified demons.

1d4 delightful demons

1. He is a kindly doctor who follows the army, healing all regardless of who they fought for. He loves healing and, if he were ever placed in a long-term situation in which there were no wounded or dying around, he would make some for himself. However, under current conditions, he doesn't need to waste time on that - there are already plenty! If the war ends he might start following another band of violent miscreants, like the PCs.
   
2. She sings at the local tavern for free. She's not especially talented on a technical level, but she enjoys it so much, it's infectious. Every so often she sings something truly beautiful, and when this happens, halfway around the world an innocent drops dead of a heart attack. She is not aware of this, and if made aware of it would not find it interesting.
   
3. It loves to see children laugh and play! It is kidnapping them to its personal Hell where it stuffs them with candy, never have the iPad taken away, and never grow old!
   
4. They whip themselves in the street: "repent! repent!" Everyone snickers that they don't really care about any of that religious stuff and just get off on the whole bit, and everyone is right.

1d4 other oddities

1. Being of axiomatic law and logic that just discovered a flaw in the nature of logic itself, and feels obliged to eliminate it as it sought to eliminate other irregularities.
2. Being of pure balance, gone excessively meta.
3. Negative energy elemental who just found out that life furthers entropy.
4. Positive energy elemental who just found out that life furthers entropy.
   

“10 monster setting" generator

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