Chapter 4

Inquiline

The Lazaret classes these parasites as inquilines, from the old word for a thing that lives inside the dwelling of another. Common folk call them latchkin. An inquiline feeds on living bodies one at a time, and what it leaves behind travels with the victim — this brood is the one a party carries away. The Lazaret’s standing instruction for it: the parasite first, then the graft.

How an inquiline works

An inquiline implants. It latches onto a living creature, feeds every round it can — each feeding adds 1 Depth — and stays until it is pulled off or has taken all it can hold. Its first feeding roots a graft in the host, and parasite and graft then grow together: the parasite on the body, riding it and feeding, and the graft inside it, beyond the reach of anything but surgery. Growth happens nowhere else. A latchling that keeps its host for days becomes its line’s next form without ever letting go, and the only inquiline that leaves a host willingly is a sated adult, off to lay.

That is what extraction is for, and why the brood is built to resist it: an attached inquiline moves with its host (Embedded), relocates against every attempt to remove it (Shift Anchor), and an attack that nearly misses it wounds the host instead. An attached inquiline is not trying to win the fight — every round attached is a meal, and it profits from any fight that lasts.

Each inquiline’s Extraction trait covers pulling the creature itself off a host. Extraction stops the feeding; it never undoes it. The graft is a separate problem, and most of this chapter is about it.

The graft

A graft is a short length of the parasite’s own tissue, left rooted in the host by its first feeding. It is a cutting in the gardener’s sense: an independent copy of its parent, already growing, and alive only while it has a body to grow in. Killing or removing the parent does not affect it.

What it looks like

Pale and threadlike at first, an inch or two long, and easy to mistake for a vein or a healed cut. It thickens as it grows; by stage 3 it stands up under the skin as a raised line, and anyone who has seen one before knows it on sight.

Which line it belongs to

A graft belongs to its parent’s line. A graft left by a latchling — which has no line yet — belongs to the line the host’s own body sets: a physical score (Strength, Dexterity, or Constitution) highest makes it sallow, Intelligence makes it chantry, Wisdom or Charisma makes it palimpsest. Each line’s graft differs:

Line	The graft	Where it roots
Sallow	Wet, pale, and soft, like a length of gut	Along the lymph, toward the deep muscle
Chantry	Fine and black, and hard as wire	Along the nerves, toward wherever the host keeps magic
Palimpsest	Almost transparent, and warm to the touch	Up the spine, toward the base of the skull

Where it is

A sallow or chantry graft has a fixed location. Roll 1d6 or choose:

1d6	Location
1-2	Arm
3-4	Leg
5	Torso
6	Head or neck

A palimpsest graft always roots in the spine, which is why no blade short of the Lazaret’s reaches one.

Depth

Depth measures how far a graft has worked into a host. It runs from 0 to 6, and it is one of the two counters in this library — the Sporophore’s Spore Load in chapter 5 runs the same 0-to-6 shape.

Gaining it

A host gains 1 Depth whenever an inquiline’s feeding action resolves against it, on a successful saving throw as well as a failed one — the save reduces what the feeding takes, never what it leaves. If the host carries no graft from that line, the feeding also leaves one. A host also gains 1 Depth at the end of every Long Rest taken while it carries a graft: the graft works inward while the body is still.

One graft per line

A host carries at most one graft from each line. Further feedings from that line deepen the graft already there — the 1d4 + 1 latchlings a clutch fastens to one character all feed the same graft. Grafts from different lines act and progress independently, and their effects stack.

At 6 Depth the graft deepens. The host contracts the line’s disease at stage 1, or advances that disease one stage if it already has it, and Depth resets to 0.

NOTE

Depth never recedes on its own. Rest does not remove it and distance does not either; the graft has to come out. The treatments below remove it.

Diagnosis

A graft announces nothing. Until its disease presents, the only ways to find one are magic and a trained eye:

Detect Poison and Disease finds every graft in range and names its line.
Examination. A creature that spends 10 minutes examining a patient makes a DC 13 Wisdom (Medicine) check — DC 16 once a disease is at stage 1 or higher. Success: The examiner finds the graft and identifies its line by its look and course (see The graft). Failure: The examiner finds nothing, and further examinations of that patient find nothing until the disease advances a stage.

Knowing what to do with the find is training, not the check. The Expulsion processes are Lazaret teaching, published with the rest of its files: a creature proficient in Medicine learned them along with its trade, wherever the order’s copies reach. An examiner without that training can find and describe a graft and not know what drives it out — a lazaret house, an officer, or a file supplies the process.

Identifying the line is the point of diagnosis. The treatments below work on every line, but Expulsion differs by line, and a patient sweated for 6 hours over a chantry graft has suffered for nothing.

Treatment

The Lazaret treats a graft in four tiers. Care slows it, Expulsion drives it out, surgery and amputation cut it out, and magic works it loose a little at a time:

Care. A creature that spends 4 hours of downtime tending the patient makes a DC 15 Wisdom (Medicine) check. Success: The graft stills, and the patient gains no Depth from the next Long Rest it finishes. Spending at least 6 hours tending the patient grants Advantage on the check.
Expulsion. A downtime procedure, different per line, that makes the body unfit to live in (see below). It removes the graft outright, at any stage and any Depth.
Surgery or amputation. Both remove the graft outright, at any stage and any Depth (see below). Neither reaches a palimpsest graft — only the Lazaret’s officers have the knowledge and skills to take one from the spine.
Magic. The restoration spells remove Depth, walking the disease back a stage (see below).

However the graft comes out, its disease ends within 1d4 hours of the removal.

Expulsion

Expulsion removes a graft by denying it, for as long as the line takes to give up, whatever that line cannot live without. A completed Expulsion removes the graft entirely — sweated out through the skin, passed, or brought up — at whatever stage and Depth it had reached.

Expulsion removes the graft, not the parasite. A host who spends 6 hours in a sweat house with a fluke still attached walks out clean and is grafted again at the next feeding — extraction comes first, always.

Line	Process	Why it works	Cost
Sallow	6 continuous hours in extreme dry heat — a sweat house, a forge floor at full fire, bare rock in high summer	The graft is water-bound and cannot follow the moisture out	3 Exhaustion levels
Chantry	24 continuous hours with no unexpended spell slot, no magical feature, no spell or magical effect targeting the host, and no magical aura or location around them	The graft feeds on magic in the body and finds none	1 Exhaustion level, and a full day of recovery after
Palimpsest	24 continuous hours spent insensible — heavily drugged, comatose, or deprived of every sense	There is nothing coherent to read, so there is nothing to take	3 Exhaustion levels, a full day of recovery after, and the cost of the insensibility

Surgery and amputation

Two procedures take a graft out through the skin:

Surgery takes 30 minutes per stage of the disease (30 minutes if none has presented), a set of tools, and a Wisdom (Medicine) check against a Difficulty Class of 10 + the disease’s stage + the graft’s Depth, made by someone other than the patient. A trained physician makes the check with Advantage; a Lazaret officer automatically succeeds on the check. Success: The graft comes out whole, and the patient takes 1d8 Slashing damage per stage of the disease (minimum 1d8). Failure: The graft stays, the patient takes the damage anyway, and further attempts on the same graft are made with Disadvantage for the next 3 days.
Amputation. If the graft is in an arm or a leg, taking the limb takes the graft, with no check. It needs a cutting tool and fire. The patient takes 33 (6d10) Slashing damage and 9 (2d8) Fire damage, gains 4 Exhaustion levels, and has lost the limb. A bone saw and a practiced hand reduce the damage to 11 (3d6) Slashing and the Exhaustion to 2 levels.

Neither procedure reaches a palimpsest graft. It roots in the spine, past any field surgery, and for that line the routes are Expulsion, magic, and the Lazaret: spinal excision is the surgery the order’s officers perform with Excise (see the officers), and they are the only surgeons who do it.

Extraction removes the parasite, not the graft. A party that pulls a cyst off a friend, binds the wound, and moves on has treated the visible half of the problem.

Magic

A restoration spell makes the body briefly reject tissue that is not its own, and what it does depends on how deeply that tissue is anchored. A parasite grips the surface, and the rejection throws it off whole — each stat block’s Extraction says which spell is enough. A graft is woven into lymph, nerve, or spine, and can only be worked loose: the spell removes Depth, and the deeper the graft sits, the less each casting moves it. One casting does both at once, detaching the parasite and removing Depth:

Spell	Depth removed
Lesser Restoration	1d4, and only below stage 3
Greater Restoration	2d4 below stage 3, or 1d4 at stage 3
Heal	3d4 below stage 3, or 2d4 at stage 3
Mass Heal	As Heal, for every creature it heals

NOTE

Magic works against the whole climb. A graft’s hold is one number: 6 Depth for each stage of its disease, plus its current Depth — a graft that has not yet caused a disease is just its current Depth. Restoration magic subtracts from that total, the disease’s stage at any moment is the total divided by 6 (rounded down), and at 0 the graft has nothing left to hold with: it comes out, and its disease ends with it.

Some examples of the climb a caster has to walk back down:

Where the host is	Depth a caster must remove
No disease yet, Depth 3	3
Stage 1, Depth 3	9
Stage 2, Depth 3	15
Stage 3, Depth 5	23

Expulsion, surgery, and amputation skip all of this; magic is the only treatment that walks back down the whole climb. Stage 4 is beyond all four tiers — see Stage 4 and each disease below.

Death and the graft

A graft eats what its host provides — flesh, magic, or memory — and two of those die with the body.

A host that dies while carrying a chantry or palimpsest graft starves it: the graft lives 1d4 days on what remains, then dies in place, and the corpse is clean. A creature raised inside that window comes back still carrying the graft, at the Depth it had; a creature raised afterward comes back clean.

The sallow line is the exception. A sallow graft feeds on flesh, and death does not take the flesh anywhere: it stays, it keeps eating, and what comes out of the body at the end is a Quagdam rather than a corpse. That is why only one of the three diseases kills — for the sallow line, the host’s death is the last step of feeding.

A Gentle Repose spell pauses both clocks for its duration: a preserved corpse neither starves its graft nor feeds it.

Laying grounds

Every sated adult leaves its host to lay, and each line lays where its food will pass. The ground an adult chooses is where a clutch waits, where the first feedings happen, and where the lancebills stand.

Line	Where it lays	What the ground looks like
Sallow	Still fresh water — fen pools, flooded fields, the warm mud below a ford	Clean-picked frogs and fish along the margin, and wading birds that never leave
Chantry	Quiet, spell-soaked places — libraries, shrines, reliquaries, a wizard’s cold rooms	Nothing. A chantry ground is indistinguishable from the room it was
Palimpsest	Where the dead are kept and the living come to remember — crypts, ossuaries	Mourners who linger too long, and caretakers who have begun to misremember small things

Latchlings die fast away from their ground. A creature that succeeds on a DC 13 Intelligence (Nature) or Wisdom (Survival) check recognizes a laying ground and the line that keeps it, as it does a brooding ground or a colony’s territory in the other broods’ chapters.

The diseases

Each line’s graft causes one disease, and every one of them ends the same way: the graft finishes, and something leaves the body. What differs is what it leaves behind.

Line	Name	Common name	At stage 4
Sallow	Sallow Rot	the wetting	The host dies. The graft stays in the corpse and matures into a Quagdam
Chantry	Chantry Drought	the emptying	The graft emerges as a Psalter Tick. The host lives on as a Lacuna
Palimpsest	—	the Forgetting	The graft emerges as a Palimpsest Wyrm. The host lives on as an Amanuensis

A graft that reaches stage 4 has eaten a whole person’s worth of what it feeds on — flesh, magic, or memory — and skips its line’s small forms accordingly. The Lacuna and the Amanuensis are not the disease; they are what is left when the disease is done.

Sallow Rot

The Lazaret files it as Sallow Rot; common folk call it the wetting. A creature contracts it at stage 1 when it reaches 6 Depth from a sallow graft:

Stage	Effect
1	The creature’s Speed decreases by 5 feet, and it gains no benefit from a Short Rest.
2	The creature’s Hit Point maximum decreases by 10, and its Speed decreases by 10 feet.
3	The creature’s Hit Point maximum decreases by a further 20, and healing it receives is halved.
4	The creature dies. The graft stays with the body and matures, 1d4 days later, into a Quagdam.

Hit Point maximum reductions last until the disease ends and do not stack with themselves — a creature at stage 3 is down 30, not 30 on top of 10.

DESIGN NOTE

Sallow Rot is the plainest disease in the library and usually the first a party meets, at low levels, from a cyst picked up in a fen. It teaches the whole system in miniature: something got in, it fed, and days later somebody is slower and does not heal right.

Chantry Drought

The Lazaret files it as Chantry Drought; common folk call it the emptying. The graft feeds on the magic in the host’s body, and the body loses the ability to hold magic as the graft advances and feeds on it. A creature contracts it at stage 1 when it reaches 6 Depth from a chantry graft.

Using magic

The graft consumes spells’ magic like any other magic in the body. Of the five spells in What magic does, only Detect Poison and Disease is safe to cast on a chantry case.

While a creature carries a chantry graft, it gains 1 Depth whenever it expends a spell slot of level 1 or higher. A Lesser Restoration, Greater Restoration, Heal, or Mass Heal spell cast on a creature carrying a chantry graft adds 1d4 Depth instead of removing any. A Lesser Restoration spell still detaches a chantry parasite, as each stat block’s Extraction says, but what would have worked the graft loose feeds it instead: the parasite drops off well fed, and the graft deepens.

Stage	Effect
1	Casting a spell of level 1 or higher costs the creature 1d6 Necrotic damage per level of the spell. This damage can’t be reduced, but Immunity to Necrotic damage prevents it.
2	One of the creature’s highest-level spell slots can’t be recovered on a Long Rest.
3	The creature’s two highest-level spell slots can’t be recovered on a Long Rest, and it has Disadvantage on Constitution saving throws made to maintain Concentration.
4	The creature loses its spellcasting entirely and has the Incapacitated and Unconscious conditions. It does not die. Over 1d4 days the graft withdraws along the nerves and emerges, swollen with a lifetime of magic, as a Psalter Tick. What wakes is a Lacuna.

DESIGN NOTE

Chantry Drought is the only disease in this library a victim can worsen by acting: each leveled spell the host casts moves it closer to stage 4. Stage 4 does not kill. The host survives as a Lacuna, the graft emerges as a Psalter Tick after 1d4 days, and both stat blocks are in this chapter.

The Forgetting

The only disease in this library the Lazaret has never formally named: the first three registrars assigned to write the file each left a different account of what it does, and the common name stood by default. A creature contracts it at stage 1 when it reaches 6 Depth from a palimpsest graft:

Stage	Effect
1	The creature loses one language, one tool proficiency, or one skill proficiency of the Game Master’s choice. It does not know it lost it; it forgets it ever had it.
2	One of the creature’s mental ability scores (Intelligence, Wisdom, or Charisma) decreases by 2, and it gains a proficiency belonging to a mind the graft’s line has eaten in the past.
3	A second mental ability score decreases by 2. The creature can no longer reliably distinguish its own memories from the ones it has been given.
4	The creature does not die. Over 1d4 days the graft uncoils from the spine and emerges, grown fat on a whole life’s recollection, as a Palimpsest Wyrm. What remains — and insists that nothing happened — is an Amanuensis.

DESIGN NOTE

The Forgetting takes things from a character without telling the player: stage 1 is written to be tracked silently, and noticed at the table only when the character reaches for what is gone. The stage 2 gain is the counterweight and is meant to be played straight — the character is genuinely better at something they were never taught, and cannot say where it came from.

The creatures

The shared larva

Every inquiline begins as a latchling, and a clutch is what a laying adult leaves behind:

Latchling

Tiny Aberration, Unaligned

A blind, mindless grub the size of a thumb joint. It fastens to a living creature and stays: its first feeding roots a graft, and days of feeding grow the latchling itself into the form its host’s nature sets. Every attaching parasite in this brood begins as a latchling, and every sated adult ends by laying a clutch of them.

AC: 13
Initiative: +3 (13)
HP: 5 (2d4)
Speed: 20 ft., Climb 20 ft., Swim 20 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	2	−4	−4	INT	3	−4	−4
DEX	16	+3	+3	WIS	10	+0	+0
CON	10	+0	+0	CHA	4	−3	−3

Skills: Stealth +7
Senses: Blindsight 10 ft., Passive Perception 10
CR: 0 (XP 10; PB +2)

Traits

Embedded. While the latchling is attached to a creature, it occupies that creature’s space, moves with it, and has Half Cover.

Extraction. While the latchling is attached, a creature within 5 feet of the host can take the Utilize action to make a DC 10 Wisdom (Medicine) check. Success: The latchling is no longer attached and lands in an unoccupied space within 5 feet of the host. Failure: The host takes 2 (1d4) Piercing damage. A Lesser Restoration spell cast on the host also ends the attachment.

Actions

Latch. Melee Attack Roll: +4, reach 5 ft. Hit: 1 Piercing damage, and if the target doesn’t already have a latchling attached, the latchling attaches to it.

Feed. The latchling draws a thread of sustenance from its host. The host gains 1 Depth and, if it carries no graft, the feeding leaves one, of the line the host’s own body sets (see What a graft is). The host notices nothing until later, as a faint tiredness following its next Long Rest. Growth: A latchling that stays attached to a host for 1d4 + 2 days grows into the form set by the host’s highest ability score — a physical score (Strength, Dexterity, or Constitution) makes a Mudspit Cyst; Intelligence, a Chantry Louse; Wisdom or Charisma, a Gaol Worm. The graft it left belongs to the same line.

Bonus Actions

Shift Anchor. While attached to a host, the latchling relocates within it. The next Extraction check made against the latchling before the start of its next turn has Disadvantage.

Running it. The latchling exists to Feed, not to fight: its attack deals 1 damage, and everything it takes goes through Feed. Left attached, it feeds, deepens its graft, and after 1d4 + 2 days is a cyst, a louse, or a worm — the encounter ends quickly; what it leaves does not. A single latchling threatens nothing; in groups, Stealth +7 still lands attachments, which is all the encounter requires.

Latchling Clutch

Medium Swarm Of Tiny Aberrations, Unaligned

Two or three hundred latchlings moving as one sheet across mud, stone, or standing water. A clutch has no purpose beyond finding bodies, and no tactics beyond arithmetic: a single latchling gets one chance to fasten, and a clutch gets three hundred.

AC: 13
Initiative: +3 (13)
HP: 90 (12d8+36)
Speed: 20 ft., Climb 20 ft., Swim 20 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	6	−2	−2	INT	3	−4	−4
DEX	16	+3	+3	WIS	10	+0	+0
CON	16	+3	+3	CHA	4	−3	−3

Resistances: Bludgeoning, Piercing, Slashing
Immunities: Charmed, Frightened, Grappled, Paralyzed, Petrified, Prone, Restrained, Stunned
Skills: Stealth +5
Senses: Blindsight 10 ft., Passive Perception 10
CR: 2 (XP 450; PB +2)

Traits

Swarm. The clutch can occupy another creature’s space and vice versa, and it can move through any opening large enough for a Tiny creature. It can’t regain Hit Points or gain Temporary Hit Points.

Everywhere at Once. A creature makes saving throws against the clutch’s Seethe with Disadvantage.

Fastened. A latchling that fastens to a creature uses the Latchling stat block and is attached to it. Each one must be removed by its own Extraction check, or a single Lesser Restoration spell cast on the host detaches every latchling attached to it at once. What a fastened latchling does next is its Feed action.

Actions

Seethe. Constitution Saving Throw: DC 13, each creature in the clutch’s space. Failure: 14 (4d6) Piercing damage, and 1d4 + 1 latchlings fasten to the target. Success: Half damage only, and one latchling fastens to the target.

Disperse. The clutch scatters into cover and is no longer a creature. It reforms in the same space at the start of its next turn, and until then it can’t be targeted or damaged. It can’t use this action if it has taken Fire damage since the end of its last turn.

Running it. The clutch exists to place latchlings; its damage is low for its Challenge Rating because latchlings are its output. Everywhere at Once means a creature in its space carries at least one latchling out of the encounter even on a successful save. Each latchling then needs its own Extraction check, or one Lesser Restoration spell clears every latchling on one creature. Disperse is unavailable after the clutch takes Fire damage, so fire is the one way to hold it in place.

The sallow line

The sallow line holds the wetlands — fens, flooded fields, fords — and it is the only line in the brood that can use a corpse. A latchling that feeds on a strong, quick, or hardy host becomes a mudspit cyst, then a sallow fluke, then something that no longer needs to ride anybody:

Mudspit Cyst

Tiny Aberration, Unaligned

A weeping gray-green sac that rides a strong or hardy host through swamp and floodplain, drinking off its vigor. It is what a latchling becomes on a body whose strength was the best thing on offer, and the first rung of the sallow line. Fed long enough, it deepens into a sallow fluke.

AC: 12
Initiative: +2 (12)
HP: 10 (4d4)
Speed: 10 ft., Swim 20 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	4	−3	−3	INT	2	−4	−4
DEX	14	+2	+2	WIS	10	+0	+0
CON	10	+0	+0	CHA	4	−3	−3

Immunities: Poison; Charmed, Frightened, Poisoned, Prone
Skills: Stealth +4
Senses: Blindsight 30 ft., Passive Perception 10
CR: 1/4 (XP 50; PB +2)

Traits

Embedded. While the cyst is attached to a creature, it occupies that creature’s space, moves with it, and has Half Cover. An attack roll against the cyst that misses by 5 or less hits the host instead, dealing the attack’s damage to the host.

Extraction. While the cyst is attached, a creature within 5 feet of the host can take the Utilize action to make a DC 11 Wisdom (Medicine) check. Success: The cyst is no longer attached and lands in an unoccupied space within 5 feet of the host. Failure: The host takes 2 (1d4) Slashing damage. A Lesser Restoration spell cast on the host also ends the attachment.

Water-Bound. The cyst dies if it ends an hour neither attached to a creature nor immersed in fresh water.

Actions

Latch. Melee Attack Roll: +4, reach 5 ft. Hit: 4 (1d4 + 2) Piercing damage. If the target is a creature that doesn’t already have a cyst attached, the cyst attaches to it.

Sap. While attached to a host, the cyst draws off the fluid in its legs. Constitution Saving Throw: DC 10, the host. Failure: 3 (1d6) Poison damage, and the host’s Speed decreases by 5 feet. Success: Half damage only, and the host’s Speed doesn’t decrease. Failure or Success: The host gains 1 Depth, and if it carries no sallow graft, the feeding leaves one. If the host’s Speed drops to 0, it has the Prone condition and can’t stand up. Speed reductions last until the host finishes a Short or Long Rest with no cyst attached.

Bonus Actions

Shift Anchor. While attached to a host, the cyst relocates within it. The next Extraction check made against the cyst before the start of its next turn has Disadvantage.

Running it. Sap accumulates: each failed save costs the host 5 feet of Speed, the reductions hold until a rest with no cyst attached, and a host that keeps failing ends the fight Prone and unable to stand. Water-Bound bounds where a cyst appears — away from fresh water it has one hour to find a host or die, which is why a lone cyst in dry country attacks at once.

Sallow Fluke

Tiny Aberration, Unaligned

A flat, pale ribbon of muscle folded against the host's spine, working the body like a bellows to draw off strength and breath. When it has taken enough, it drops away into warm mud to lay, and the cycle starts again.

AC: 13
Initiative: +3 (13)
HP: 22 (5d4+10)
Speed: 5 ft., Swim 30 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	3	−4	−4	INT	4	−3	−3
DEX	16	+3	+5	WIS	12	+1	+1
CON	14	+2	+4	CHA	6	−2	−2

Resistances: Bludgeoning, Piercing, Slashing
Immunities: Poison; Charmed, Exhaustion, Frightened, Poisoned, Prone
Skills: Stealth +5
Senses: Blindsight 60 ft., Passive Perception 11
CR: 1 (XP 200; PB +2)

Traits

Embedded. While the fluke is attached to a creature, it occupies that creature’s space, moves with it, and has Half Cover. An attack roll against the fluke that misses by 5 or less hits the host instead, dealing the attack’s damage to the host.

Extraction. While the fluke is attached, a creature within 5 feet of the host can take the Utilize action to make a DC 13 Wisdom (Medicine) check. Success: The fluke is no longer attached and lands in an unoccupied space within 5 feet of the host. Failure: The host takes 3 (1d6) Slashing damage. A Lesser Restoration spell cast on the host also ends the attachment.

Water-Bound. The fluke dies if it ends an hour neither attached to a creature nor immersed in fresh water.

Actions

Bore. Melee Attack Roll: +5, reach 5 ft. Hit: 7 (1d8 + 3) Piercing damage. If the target is a creature that doesn’t already have a fluke attached, the fluke attaches to it.

Deepen. While attached to a host, the fluke feeds. Constitution Saving Throw: DC 12, the host. Failure: 5 (2d4) Necrotic damage, and the host’s Hit Point maximum decreases by an amount equal to the damage taken. Success: Half damage only, and the host’s Hit Point maximum doesn’t decrease. Failure or Success: The host gains 1 Depth, and if it carries no sallow graft, the feeding leaves one. If the host’s Hit Point maximum drops to 0, it dies. Reductions last until the host finishes a Long Rest with no fluke attached.

Bonus Actions

Shift Anchor. While attached to a host, the fluke relocates within it. The next Extraction check made against the fluke before the start of its next turn has Disadvantage.

Running it. Weapon attacks answer an embedded fluke poorly: it resists all three physical damage types, and Embedded’s near-miss clause sends failed attacks into the host. Extraction is the built-in solution and Shift Anchor its counter. Deepen is the first effect in the library that can kill a host outright, and its Hit Point maximum reduction survives the fight until a Long Rest taken without the fluke.

Mire Ambulant

Medium Aberration, Unaligned

A fluke grown to the length of an arm, with a broad muscular foot along its underside. It walks wet ground at a man's pace with its upper third raised, and it no longer depends on finding a host. It fastens on when it chooses to.

AC: 15
Initiative: +2 (12)
HP: 104 (11d8+55)
Speed: 30 ft., Swim 40 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	16	+3	+3	INT	6	−2	−2
DEX	14	+2	+2	WIS	12	+1	+1
CON	20	+5	+7	CHA	8	−1	−1

Resistances: Bludgeoning, Piercing, Slashing
Immunities: Poison; Charmed, Exhaustion, Frightened, Poisoned, Prone
Senses: Blindsight 60 ft., Passive Perception 11
CR: 4 (XP 1,100; PB +2)

Traits

Embedded. While the ambulant is attached to a creature, it occupies that creature’s space, moves with it, and has Half Cover. An attack roll against the ambulant that misses by 5 or less hits the host instead, dealing the attack’s damage to the host.

Extraction. While the ambulant is attached, a creature within 5 feet of the host can take the Utilize action to make a DC 15 Wisdom (Medicine) check. Success: The ambulant is no longer attached and lands in an unoccupied space within 5 feet of the host. Failure: The host takes 9 (2d8) Slashing damage. A Lesser Restoration spell cast on the host also ends the attachment.

Water-Bound. The ambulant dies if it ends an hour neither attached to a creature nor immersed in fresh water.

Actions

Multiattack. The ambulant makes two Bore attacks. It can replace one attack with a use of Deepen.

Bore. Melee Attack Roll: +5, reach 5 ft. Hit: 13 (2d10 + 3) Piercing damage. If the target is a creature that doesn’t already have an inquiline attached, the ambulant attaches to it.

Deepen. While attached to a host, the ambulant feeds. Constitution Saving Throw: DC 15, the host. Failure: 11 (2d10) Necrotic damage, and the host’s Hit Point maximum decreases by an amount equal to the damage taken. Success: Half damage only, and the Hit Point maximum doesn’t decrease. Failure or Success: The host gains 1 Depth, and if it carries no sallow graft, the feeding leaves one.

Bonus Actions

Shift Anchor. While attached to a host, the ambulant relocates within it. The next Extraction check made against the ambulant before the start of its next turn has Disadvantage.

Running it. An ambulant no longer needs a host and behaves accordingly: it fights at reach, withdraws into water when hurt, and attaches only to a target already down or held. It resists the three physical damage types and swims at 40 feet, so a party without a way to hold it in place fights it more than once.

Quagdam

Large Aberration, Unaligned

The end of the sallow line: a pale sac the size of a rowing boat, half sunk in mud, ringed by the boring mouths of its partly grown young. It never leaves the water. It spends its life producing latchlings and feeding on whatever comes to the edge.

AC: 17
Initiative: +1 (11)
HP: 138 (12d10+72)
Speed: 20 ft., Swim 50 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	20	+5	+5	INT	7	−2	−2
DEX	12	+1	+1	WIS	14	+2	+6
CON	22	+6	+10	CHA	10	+0	+0

Resistances: Bludgeoning, Piercing, Slashing
Immunities: Poison; Charmed, Exhaustion, Frightened, Poisoned, Prone
Senses: Blindsight 90 ft., Passive Perception 12
CR: 9 (XP 5,000; PB +4)

Traits

Water-Bound. The quagdam dies if it ends an hour out of fresh water.

Gravid. The quagdam carries a clutch at all times. When it drops to 0 Hit Points, a Latchling Clutch emerges from the body in its space.

Actions

Multiattack. The quagdam makes three Bore attacks. It can replace one attack with a use of Draw Down.

Bore. Melee Attack Roll: +9, reach 10 ft. Hit: 22 (4d8 + 5) Piercing damage.

Draw Down. Constitution Saving Throw: DC 18, one creature the quagdam can see within 30 feet. Failure: 22 (4d10) Necrotic damage, the target’s Hit Point maximum decreases by an amount equal to the damage taken, and the quagdam regains Hit Points equal to half the damage. Success: Half damage only, and the Hit Point maximum doesn’t decrease. Failure or Success: The target gains 1 Depth, and if it carries no sallow graft, the feeding leaves one.

Reactions

Spill. Trigger: The quagdam takes 20 damage or more from a single attack. Response: Partly grown young come out of the wound. Each creature within 10 feet of the quagdam makes a DC 18 Dexterity saving throw, taking 14 (4d6) Piercing damage on a failed save or half as much on a successful one.

Running it. The quagdam cannot leave the water and never has to: Draw Down reaches 30 feet, heals it for half of what it takes, and is the brood’s only feeding that works at range — it grafts a party rather than a person. Gravid means killing it does not end the encounter; a Latchling Clutch emerges when it drops to 0 Hit Points.

The chantry line

The chantry line grows on casters, and every stage after the first is harder, quieter, and better at hiding what it is doing:

Chantry Louse

Tiny Aberration, Unaligned

A black, chitinous tick the size of a fist that clings behind the ear and drinks the magic in a caster's blood. A latchling that fed on a body bright with magic hardens into one. Sated, it withdraws to a quiet, spell-soaked place to lay.

AC: 14
Initiative: +3 (13)
HP: 45 (10d4+20)
Speed: 10 ft., Climb 20 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	5	−3	−3	INT	11	+0	+0
DEX	17	+3	+5	WIS	14	+2	+4
CON	15	+2	+2	CHA	14	+2	+2

Resistances: Force, Psychic
Immunities: Poison; Charmed, Frightened, Poisoned, Prone
Skills: Arcana +2, Stealth +5
Senses: Blindsight 30 ft., Passive Perception 12
Languages: understands Common but can’t speak
CR: 3 (XP 700; PB +2)

Traits

Embedded. While the louse is attached to a creature, it occupies that creature’s space, moves with it, and has Half Cover. An attack roll against the louse that misses by 5 or less hits the host instead, dealing the attack’s damage to the host.

Extraction. While the louse is attached, a creature within 5 feet of the host can take the Utilize action to make a DC 14 Wisdom (Medicine) check. Success: The louse is no longer attached and lands in an unoccupied space within 5 feet of the host. Failure: The host takes 5 (2d4) Slashing damage. A Lesser Restoration spell cast on the host also ends the attachment.

Arcane Tropism. The louse has Advantage on attack rolls against a creature that is Concentrating or that has expended a spell slot since the end of the louse’s last turn.

Actions

Proboscis. Melee Attack Roll: +5, reach 5 ft. Hit: 8 (1d10 + 3) Piercing damage. If the target is a creature that doesn’t already have a louse attached, the louse attaches to it.

Siphon. While attached to a host, the louse drinks the magic in its blood. Charisma Saving Throw: DC 12, the host. Failure: 10 (3d6) Force damage, and the host loses its lowest-level unexpended spell slot. Success: Half damage only, and the host loses no slot. Failure or Success: The host gains 1 Depth, and if it carries no chantry graft, the feeding leaves one. If the host has no unexpended spell slots, it takes an extra 3 (1d6) Force damage.

Bonus Actions

Shift Anchor. While attached to a host, the louse relocates within it. The next Extraction check made against the louse before the start of its next turn has Disadvantage.

Reactions

Backwash. Trigger: The host casts a spell with a level of 1 or higher. Response: Constitution Saving Throw: DC 12, the host. Failure: 7 (2d6) Psychic damage, and the host has Disadvantage on the next saving throw it makes to maintain Concentration. Success: Half damage only.

Running it. The louse taxes one caster three ways: Siphon takes a spell slot, Backwash punishes casting, and Arcane Tropism rewards attacking whoever just cast. Siphon takes the lowest unexpended slot first, so the exchange runs for several rounds rather than ending on one save. A Lesser Restoration spell detaches it — the louse drops off unhurt and well fed, and the graft it left is already inside.

Psalter Tick

Small Aberration, Unaligned

A fist of something between chitin and slate, marked across the back with pale lines that read as writing in no known hand. It is a chantry louse grown past its shell twice over — or a chantry graft that finished its work and climbed out already this size. It has begun to use the magic it takes.

AC: 16
Initiative: +4 (14)
HP: 142 (19d6+76)
Speed: 20 ft., Climb 30 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	8	−1	−1	INT	14	+2	+2
DEX	18	+4	+7	WIS	14	+2	+5
CON	18	+4	+4	CHA	16	+3	+3

Resistances: Force, Psychic
Immunities: Poison; Charmed, Frightened, Poisoned, Prone
Skills: Arcana +5, Stealth +7
Senses: Blindsight 30 ft., Passive Perception 12
Languages: understands Common and Deep Speech but can’t speak
CR: 7 (XP 2,900; PB +3)

Traits

Embedded. While the tick is attached to a creature, it occupies that creature’s space, moves with it, and has Half Cover. An attack roll against the tick that misses by 5 or less hits the host instead, dealing the attack’s damage to the host.

Extraction. While the tick is attached, a creature within 5 feet of the host can take the Utilize action to make a DC 16 Wisdom (Medicine) check. Success: The tick is no longer attached and lands in an unoccupied space within 5 feet of the host. Failure: The host takes 10 (3d6) Slashing damage. A Lesser Restoration spell cast on the host also ends the attachment.

Arcane Tropism. The tick has Advantage on attack rolls against a creature that is Concentrating or that has expended a spell slot since the end of the tick’s last turn.

Stolen Slots. The tick keeps every spell slot it takes with Siphon, to a maximum of five at a time. It can expend one to cast a spell of that level or lower from the list below, using Charisma as its spellcasting ability (spell save DC 14). Spells: Detect Magic, Exacerbation, Magic Missile, Misty Step, Chantry Tithe, Counterspell, Dispel Magic

Actions

Multiattack. The tick makes two Proboscis attacks. It can replace one attack with a use of Siphon or with one spell.

Proboscis. Melee Attack Roll: +7, reach 5 ft. Hit: 20 (3d10 + 4) Piercing damage. If the target is a creature that doesn’t already have an inquiline attached, the tick attaches to it.

Siphon. While attached to a host, the tick drinks the magic in its blood. Charisma Saving Throw: DC 15, the host. Failure: 17 (5d6) Force damage, and the host loses its lowest-level unexpended spell slot, which the tick keeps. Success: Half damage only, and the host loses no slot. Failure or Success: The host gains 1 Depth, and if it carries no chantry graft, the feeding leaves one. If the host has no unexpended spell slots, it takes an extra 7 (2d6) Force damage.

Bonus Actions

Shift Anchor. While attached to a host, the tick relocates within it. The next Extraction check made against the tick before the start of its next turn has Disadvantage.

Reactions

Backwash. Trigger: The host casts a spell with a level of 1 or higher. Response: Constitution Saving Throw: DC 15, the host. Failure: 10 (3d6) Psychic damage, and the host has Disadvantage on the next saving throw it makes to maintain Concentration. Success: Half damage only.

Running it. Stolen Slots starts empty: everything the tick can do beyond biting has to be taken from the party first, which makes the opening round the cheapest one. A taken slot can come back as Counterspell or Dispel Magic, and Misty Step is on the list so a sated tick can leave.

Choirgall

Medium Aberration, Unaligned

The last chantry stage: a hollow shell of bone and hardened tissue the size of a bell, grown outward through the caster it finished on. It has taken enough magic to make its own, and what comes out of it is closer to sound than to spellwork.

AC: 17
Initiative: +11 (21)
HP: 195 (23d8+92)
Speed: 30 ft., Climb 30 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	12	+1	+1	INT	18	+4	+8
DEX	16	+3	+3	WIS	16	+3	+7
CON	18	+4	+8	CHA	20	+5	+9

Resistances: Force, Psychic
Immunities: Poison; Charmed, Deafened, Frightened, Poisoned
Skills: Arcana +8, Perception +7
Senses: Blindsight 60 ft., Truesight 30 ft., Passive Perception 17
Languages: Common, Deep Speech
CR: 12 (XP 8,400; PB +4)

Traits

Legendary Resistance (3/Day). If the choirgall fails a saving throw, it can choose to succeed instead.

Arcane Tropism. The choirgall has Advantage on attack rolls against a creature that is Concentrating or that has expended a spell slot since the end of the choirgall’s last turn.

Sympathetic Resonance. Whenever a creature within 60 feet of the choirgall casts a spell of level 1 or higher, the choirgall gains 5 Temporary Hit Points and its next Antiphon deals an extra 5 (2d4) Force damage.

Spellcasting

Casts using CHA as the spellcasting ability, spell save DC 17, +9 to hit with spell attacks.

At Will: Anamnesis

1/Day Each: Bloom Interdict

Actions

Multiattack. The choirgall makes three Chime attacks. It can replace one attack with a use of Antiphon.

Chime. Melee Attack Roll: +9, reach 10 ft. Hit: 14 (2d10 + 3) Bludgeoning damage plus 9 (2d8) Force damage.

Antiphon (1/Day). The shell sounds once, and the note arrives everywhere at the same moment. Constitution Saving Throw: DC 17, each creature in a 30-foot Emanation originating from the choirgall. Failure: 36 (8d8) Force damage, and the target can’t cast a spell that requires a Verbal component until the end of its next turn. Success: Half damage only.

Unmake (1/Day). The choirgall picks a magical effect apart rather than dispelling it. Choose one magical effect within 60 feet that is a spell of level 5 or lower. The effect ends, and the creature that created it takes 27 (6d8) Force damage and has Disadvantage on the next spell attack roll it makes.

Reactions

Discord. Trigger: A creature within 60 feet of the choirgall succeeds on a saving throw against one of its effects. Response: That creature takes 9 (2d8) Psychic damage.

Running it. The choirgall is fed by casting near it: Sympathetic Resonance stacks across a round, and Antiphon and Unmake are each once a day, so its early rounds are Chime and patience. It is the one inquiline that never attaches — its host is already spent — so nothing in this fight is about pulling something off a friend.

The palimpsest line

The palimpsest line feeds on memory. It grows slowest, roots deepest, and is the only line whose graft no blade outside the Lazaret reaches:

Gaol Worm

Small Aberration, Unaligned

A long, sightless burrower that threads down the spine of a wise or strong-willed host and feeds on memory, walling off recollection a piece at a time. Its host stops truly resting. Given years and enough forgetting, it thickens toward the palimpsest wyrm.

AC: 15
Initiative: +3 (13)
HP: 85 (10d6+50)
Speed: 20 ft., Burrow 20 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	12	+1	+1	INT	5	−3	−3
DEX	17	+3	+3	WIS	14	+2	+5
CON	20	+5	+8	CHA	7	−2	−2

Resistances: Necrotic
Immunities: Poison; Charmed, Exhaustion, Frightened, Poisoned, Prone
Skills: Stealth +6
Senses: Blindsight 60 ft., Tremorsense 60 ft., Passive Perception 12
CR: 6 (XP 2,300; PB +3)

Traits

Embedded. While the worm is attached to a creature, it occupies that creature’s space, moves with it, and has Half Cover. An attack roll against the worm that misses by 5 or less hits the host instead, dealing the attack’s damage to the host.

Extraction. While the worm is attached, a creature within 5 feet of the host can take the Utilize action to make a DC 16 Wisdom (Medicine) check. Success: The worm is no longer attached and lands in an unoccupied space within 5 feet of the host. Failure: The host takes 7 (2d6) Slashing damage. A Lesser Restoration spell cast on the host also ends the attachment.

Sleepless. A creature that has a gaol worm attached gains no benefit from a Long Rest.

Actions

Multiattack. The worm makes two Rasp attacks.

Rasp. Melee Attack Roll: +6, reach 5 ft. Hit: 12 (2d8 + 3) Piercing damage. If the target is a creature that doesn’t already have a worm attached, the worm attaches to it.

Wear Down. While attached to a host, the worm keeps it from ever resting. Constitution Saving Throw: DC 16, the host. Failure: 18 (4d8) Necrotic damage, and the host gains 1 Exhaustion level. Success: Half damage only, and the host gains no Exhaustion level. Failure or Success: The host gains 1 Depth, and if it carries no palimpsest graft, the feeding leaves one.

Bonus Actions

Shift Anchor. While attached to a host, the worm relocates within it. The next Extraction check made against the worm before the start of its next turn has Disadvantage.

Reactions

Convulse. Trigger: The worm takes damage while attached to a host. Response: Constitution Saving Throw: DC 16, the host. Failure: 9 (2d8) Necrotic damage, and the host has the Poisoned condition until the end of its next turn. Success: Half damage only.

Running it. Convulse redirects the party’s damage into the host: every hit on an attached worm costs the host a saving throw. Sleepless persists between encounters — the host gains no benefit from a Long Rest until the worm is off — so the worm is an ongoing condition as much as a fight, and either Rasp can attach it to a second target.

Palimpsest Wyrm

Medium Aberration, Unaligned

The memory line's final shape: a coiled, pale thing grown fat on stolen recollection. It does not merely eat a mind — it overwrites one, smearing the host's memories under the record of everything it has taken before. It lays where the dead are kept, so its latchlings hatch surrounded by minds.

AC: 17
Initiative: +4 (14)
HP: 161 (19d8+76)
Speed: 20 ft., Climb 20 ft., Swim 30 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	10	+0	+0	INT	18	+4	+8
DEX	18	+4	+8	WIS	16	+3	+7
CON	18	+4	+8	CHA	15	+2	+2

Resistances: Cold, Necrotic
Immunities: Poison, Psychic; Charmed, Exhaustion, Frightened, Poisoned, Prone
Skills: Deception +6, Insight +7, Perception +7, Stealth +8
Senses: Truesight 60 ft., Passive Perception 17
Languages: Deep Speech, telepathy 120 ft.
CR: 11 (XP 7,200; PB +4)

Traits

Embedded. While the wyrm is attached to a creature, it occupies that creature’s space, moves with it, and has Half Cover. An attack roll against the wyrm that misses by 5 or less hits the host instead, dealing the attack’s damage to the host.

Extraction. While the wyrm is attached, a creature within 5 feet of the host can take the Utilize action to make a DC 19 Wisdom (Medicine) check. Success: The wyrm is no longer attached and lands in an unoccupied space within 5 feet of the host. Failure: The host takes 13 (3d8) Slashing damage. A Greater Restoration spell cast on the host also ends the attachment.

Written Over. While attached to a host, the wyrm knows everything the host knows, can speak in the host’s voice, and has Advantage on Charisma (Deception) checks made to impersonate it.

Actions

Multiattack. The wyrm makes two Stylus attacks. It can replace one attack with a use of Overwrite if it is attached to a host.

Stylus. Melee Attack Roll: +8, reach 10 ft. Hit: 15 (2d10 + 4) Piercing damage plus 9 (2d8) Psychic damage. If the target is a creature that doesn’t already have a wyrm attached, the wyrm attaches to it.

Overwrite. While attached to a host, the wyrm rewrites what it finds there. Intelligence Saving Throw: DC 16, the host. Failure: 22 (4d10) Psychic damage, and the host’s Intelligence, Wisdom, or Charisma score (the wyrm’s choice) decreases by 2. Success: Half damage only, and no score decreases. Failure or Success: The host gains 1 Depth, and if it carries no palimpsest graft, the feeding leaves one. If any of the host’s scores drops to 0, the host has the Unconscious condition until it finishes a Long Rest. Score reductions last until removed by a Greater Restoration spell or similar magic.

Erase (Recharge 5–6). Wisdom Saving Throw: DC 16, each creature in a 30-foot Emanation originating from the wyrm. Failure: 27 (6d8) Psychic damage, and the target can’t use any feature or trait that has a limited number of uses until the end of its next turn. Success: Half damage only.

Bonus Actions

Shift Anchor. While attached to a host, the wyrm relocates within it. The next Extraction check made against the wyrm before the start of its next turn has Disadvantage.

Reactions

Bleed Through. Trigger: The wyrm takes damage while attached to a host. Response: Constitution Saving Throw: DC 16, the host. Failure: 13 (3d8) Psychic damage. Success: Half damage only.

Running it. Written Over works before initiative: an attached wyrm knows everything its host knows and can speak in its voice. Erase suppresses limited-use features across a 30-foot Emanation for a round. It is the only inquiline a Lesser Restoration spell does not detach; removal takes the DC 19 Extraction check or a Greater Restoration spell.

What is left

Two of the three diseases end with the host still walking. Neither creature below is a parasite, and neither has one in it any more:

Lacuna

Medium Humanoid, Neutral

A caster with the magic taken out, and more than the magic. A lacuna eats, sleeps, and answers to its name, and there is nothing behind any of it. Left alone, it goes through the motions of its old work in its old places for as long as someone keeps feeding it.

AC: 12
Initiative: +1 (11)
HP: 91 (14d8+28)
Speed: 30 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	12	+1	+1	INT	8	−1	−1
DEX	12	+1	+1	WIS	10	+0	+0
CON	14	+2	+2	CHA	3	−4	−4

Immunities: Charmed, Frightened
Senses: Passive Perception 10
Languages: the languages it knew before
CR: 2 (XP 450; PB +2)

Traits

Nothing to Take. No inquiline will graft to a lacuna, and none can feed on one. Effects that read, compel, or alter a creature’s mind fail against it, because there is nothing left in the way that such effects need something to work on.

Drawn to Casting. On its turn, the lacuna moves toward the nearest creature it can see that has cast a spell since the start of the lacuna’s last turn, and attacks that creature if it can reach it. It does not attack anything else while such a creature is in sight.

Actions

Multiattack. The lacuna makes two Strike attacks.

Strike. Melee Attack Roll: +3, reach 5 ft. Hit: 11 (2d8 + 1) Bludgeoning damage.

Reactions

Empty Casting. Trigger: A creature the lacuna can see within 30 feet casts a spell. Response: The lacuna performs the same words and gestures alongside it, correctly and completely, and nothing happens. Wisdom Saving Throw: DC 12, the triggering creature. Failure: The creature has Disadvantage on attack rolls against the lacuna until the end of its next turn.

Running it. A lacuna’s stat block exists for one moment: Drawn to Casting sends it, without malice, at whoever last cast a spell, past everyone else in the room. Empty Casting deals no damage because nothing happens when a lacuna casts. It cannot be infected and cannot be read, and the Lazaret uses lacunas to carry things through country nobody else will enter. They do not object to anything.

Amanuensis

Medium Humanoid, Neutral Evil

A complete person assembled out of other people. The wyrm that left its spine is long gone; what remains walks, talks, remembers, and holds opinions, running on memories that were never its own — and it is entirely convinced they are.

AC: 14
Initiative: +2 (12)
HP: 136 (16d8+64)
Speed: 30 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	14	+2	+2	INT	16	+3	+3
DEX	14	+2	+2	WIS	14	+2	+5
CON	18	+4	+4	CHA	18	+4	+7

Immunities: Charmed
Skills: Deception +10, Insight +5, Perception +5, Persuasion +7
Senses: Passive Perception 15
Languages: Common and every language any of its sources knew
CR: 5 (XP 1,800; PB +3)

Traits

Insists. The amanuensis believes it is who it was. It cannot be detected as lying about its own identity or history by any magical means, including a Zone of Truth spell, because it is not lying.

Borrowed Hands. The amanuensis has proficiency in every skill and tool that any of its sources had. In practice a Game Master should let it be unexpectedly competent at one specific thing per scene.

Actions

Multiattack. The amanuensis makes two Strike attacks.

Strike. Melee or Ranged Attack Roll: +5, reach 5 ft. or range 30/120 ft. Hit: 17 (4d6 + 2) Bludgeoning, Piercing, or Slashing damage, depending on what it carries.

Reactions

Parry. Trigger: The amanuensis is hit by a melee attack roll while it is holding a weapon. Response: It adds 3 to its Armor Class against that attack, possibly causing it to miss.

Running it. The amanuensis is built as a social encounter with a stat block underneath it. Insists means divination confirms its story, because from the inside the story is true — a Zone of Truth spell clears it. Borrowed Hands is intended as one unexpected competence per scene, and its weapon is the clearest surviving trace of the person it believes it is.

One who hunts them

The lancebill is not an inquiline. It is in this library because a party dealing with one will meet it, and because it can remove a graft:

Lancebill

Large Monstrosity, Unaligned

A wading bird the height of a horse, gray-white and long-necked, standing motionless in the shallows for hours. Lancebills eat parasites and nothing else. They can tell an infected creature from a clean one at a hundred paces, and they take what they came for through whatever is in the way.

AC: 15
Initiative: +4 (14)
HP: 168 (16d10+80)
Speed: 40 ft., Swim 40 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	18	+4	+4	INT	4	−3	−3
DEX	18	+4	+7	WIS	16	+3	+6
CON	20	+5	+5	CHA	8	−1	−1

Skills: Perception +9, Stealth +10
Senses: Darkvision 60 ft., Passive Perception 19
CR: 8 (XP 3,900; PB +3)

Traits

Parasite Sense. The lancebill knows the location of every creature within 120 feet that is carrying an inquiline or a graft, and can tell which.

Standing. The lancebill has Advantage on Dexterity (Stealth) checks while it has not moved since the end of its last turn.

Actions

Multiattack. The lancebill makes three Bill attacks. It can replace one attack with a use of Lance.

Bill. Melee Attack Roll: +7, reach 10 ft. Hit: 18 (3d8 + 4) Piercing damage.

Lance. Melee Attack Roll: +7, reach 15 ft., one creature carrying an inquiline or a graft. Hit: 22 (4d8 + 4) Piercing damage, and the lancebill takes what it was aiming for. An attached inquiline is pulled off and swallowed, or a graft is drawn out whole and swallowed, ending the disease it was causing.

Running it. Lance is a cure delivered by something that does not stop at one: it takes a graft out of an unconscious ally, a prisoner, or the party’s healer with the same stroke, and keeps hunting afterward because there is usually more than one. Parasite Sense means a grafted party in wet country is already being tracked, and Standing means the tracker is not seen until it moves.

The apex

Exemplar

Gargantuan Aberration, Neutral Evil

The first latchling, which never stopped feeding. Everything in the brood descends from it. The body is a pale coil some sixty feet long, buried through a hillside or a lake bed with a few loops showing, studded along its whole length with the partly absorbed remains of what it has taken — most of them still moving a little. Hosts are brought to it now, or it comes up underneath them.

AC: 19
Initiative: +14 (24)
HP: 310 (20d20+100)
Speed: 30 ft., Burrow 30 ft., Swim 60 ft.

Ability	Score	Mod	Save	Ability	Score	Mod	Save
STR	26	+8	+8	INT	22	+6	+12
DEX	14	+2	+8	WIS	20	+5	+11
CON	20	+5	+11	CHA	20	+5	+5

Resistances: Bludgeoning, Piercing, Slashing
Immunities: Poison; Charmed, Exhaustion, Frightened, Paralyzed, Poisoned, Prone
Skills: Insight +12, Perception +12
Senses: Tremorsense 120 ft., Truesight 120 ft., Passive Perception 22
Languages: Deep Speech, telepathy 1 mile
CR: 17 (XP 18,000; PB +6)

Traits

Legendary Resistance (3/Day). If the exemplar fails a saving throw, it can choose to succeed instead.

The First. Every inquiline within 5 miles is aware of the exemplar and will not attack it or anything attached to it. The exemplar can perceive through any of them at will.

Never Stopped. The exemplar regains 20 Hit Points at the start of each of its turns. This trait doesn’t function if it took Fire or Radiant damage since the end of its last turn.

Actions

Multiattack. The exemplar makes three Bore attacks. It can replace one attack with a use of Seed.

Bore. Melee Attack Roll: +14, reach 15 ft. Hit: 35 (5d10 + 8) Piercing damage, and the target has the Grappled condition (escape DC 20) if it is Large or smaller.

Take In. One creature Grappled by the exemplar is drawn into the coil. The target has the Restrained and Blinded conditions, takes 27 (6d8) Necrotic damage at the start of each of the exemplar’s turns, and gains 1 Depth each time it takes that damage, gaining a graft as Seed does if it carries none. A creature can escape with a successful DC 20 Strength (Athletics) check, and the exemplar can hold up to four creatures this way.

Seed. Constitution Saving Throw: DC 21, each creature in a 30-foot Emanation originating from the exemplar. Failure: 33 (6d10) Piercing damage, and the target gains 2 Depth. Success: Half damage only, and the target gains 1 Depth. Failure or Success: A target that carries no graft gains one, of the line its own body sets (see What a graft is).

Legendary Actions (3/round)

Immediately after another creature’s turn, this creature can expend a use to take one of the following actions. It regains all expended uses at the start of each of its turns.

Shift. The exemplar burrows up to half its Speed without provoking Opportunity Attacks, carrying anything it has taken in. It can’t take this action again until the start of its next turn.

Draw. One creature Grappled by the exemplar is subjected to Take In. It can’t take this action again until the start of its next turn.

Speak. The exemplar drives its attention through the brood and into one mind. It targets one creature within 1 mile that is carrying an inquiline or a graft, or that is within 60 feet of one. Wisdom Saving Throw: DC 21, that creature. Failure: 21 (6d6) Psychic damage, and the target has Disadvantage on the next saving throw it makes before the end of its next turn. Success: Half damage only. The exemplar can’t take this action again until the start of its next turn. What the creature experiences is not sound. It is being read, all at once, by something old enough to have read everything else.

Running it. Seed grafts the whole party within three rounds regardless of rolls, so the fight is not the expensive part of this encounter — what the party carries out of it is. Take In and Draw remove up to four characters from the fight while Never Stopped regenerates through everything except Fire and Radiant damage. The First means every graft the party has ever carried descends from this creature, and that it perceives through all of them.