Xanthoria

• An Adventure for 16th-level Characters

• Edited by Kim Mohan

• Developed by Bill Benham & Christopher Perkins

• Written by Toni Winslow-Brill

A deadly fungal infection called the saprophytic plague is ravaging the Sword Coast. The plague not only targets beasts and humanoids but also destroys crops and stored foodstuffs, causing famine and sickness on an epic scale. Religious and civil authorities are unable to stem the tide of the saprophytic plague, and even a wish spell can’t undo the contagion, given how widespread it has become.

The mystery surrounding Xanthoria has to do with the discovery of a mad druid’s quest for lichdom and the plague she unleashed in the process. Ordinary liches contain their souls in inanimate objects, but the druid Xanthoria discovered a way to house her soul in a living being.

Beginning the Adventure

Read the following boxed text to the players to kick off the adventure:

A fungal plague is ravaging the Sword Coast, spreading quickly from one settlement to the next. Although magic has proven effective at ridding individuals of the spore infection, the plague is spreading too quickly to contain. Creatures that become infected fall ill with a fever and sprout disgusting, gooey, fungal growths before losing their autonomy, acting like zombies. They also release spores that infect other beasts and humanoids. Eventually, the plague reduces all infected creatures and foodstuffs to puddles of ooze.

Humanoids infected with the plague drone the word “Xanthoria” over and over for no discernible reason before death finally claims them. You have determined that there’s a book by that name contained in the library-fortress of Candlekeep. With luck, the book holds information that might help you end the saprophytic plague before it wipes out every village, town, and city in Faerûn.

Xanthoria was a powerful druid who transformed herself into a lichen lich (see area the end of the adventure for a description of this new monster). Liches typically use inanimate objects as phylacteries, but Xanthoria discovered a way to house her soul in a living sprite named Thunderwing. Though initially concerned with ways to end the unnatural life of the undead, Xanthoria’s research took a dark turn as her madness bloomed. The book titled Xanthoria chronicles her descent into madness.

The Saprophytic Plague

Xanthoria’s research into lichdom and her creation of a living phylactery led to the emergence of the plague spreading across the Sword Coast. Any beast or humanoid that comes within 10 feet of a creature infected by the saprophytic plague must succeed on a DC 20 Constitution saving throw or become infected as well. On a successful save, a creature is immune to the plague for 24 hours, and any creature that is immune to disease succeeds on the save automatically.

After a failed save, a creature experiences the first symptoms—body aches, nausea, slurred speech, and uncontrollable drooling—1d4 hours later and gains 1 level of exhaustion. Every 24 hours thereafter, the creature automatically gains another level of exhaustion. Any creature killed by the saprophytic plague transforms into a lifeless magenta ooze.

A creature infected by the saprophytic plague for at least 24 hours behaves like a zombie and seems barely aware of its surroundings, as fungal growths sprout from its head, body, and limbs. It feels an overriding urge to be around groups of uninfected creatures so that it can spread the contagion. This is the time when infected humanoids begin speaking the word “Xanthoria” over and over, with no understanding of what the word means. This behavior is the result of a mycelial network of spores that forms a tenuous connection between Xanthoria and humanoids that become infected by the plague.

Foodstuffs that are exposed to the plague’s spores decay or go sour within 2d12 hours, leaving behind a lurid magenta mass of oozing fungi. Eating infected food requires a saving throw as above.

Any magic that cures a disease can rid a creature of the saprophytic plague. Casting purify food and drink destroys the infection in foodstuffs.

Finding the Book

Upon arriving in Candlekeep, the characters can use an Avowed guide to help them track down the book titled Xanthoria. This quest brings them to the attention of Zelyth Lightleaf, one of Candlekeep’s sages and the foremost expert on Xanthoria—both the book and its mysterious author:

Your guide does not return. Instead, you are greeted by a robed wood elf with brown hair and a plain face. In her hands, she holds a book so encrusted with lichen that its covers can barely be closed around its wrinkled pages. “I believe you’re looking for this,” she says with a warm, bright smile. “My name is Zelyth Lightleaf. I’m Candlekeep’s foremost expert on this book and its author.”

A few months ago, Zelyth Lightleaf (neutral good wood elf sage; see the “Candlekeep” section at area the front of the book for her stat block) joined the Avowed, using the book as her entrance gift into the library. She found it in an abandoned satchel near a secluded cave system called the Lykortha Expanse, which is known among druids for its rare fungal growths. Zelyth assumed the book had been lost and took possession of it.

Quiet and unassuming, Zelyth concentrates on training new acolytes and tending to those in need, but she’s aware of the fungal plague spreading like wildfire up and down the Sword Coast. She has been expecting someone to show up looking for the book.

Zelyth allows the characters to peruse the book and assures them it’s safe to do so. (The lichen covering the book poses no danger.) She also shares the following information with the characters:

• Xanthoria was a druid of Silvanus (god of wild nature) whose forest home was threatened by undead. By researching fungi and lichen, Xanthoria hoped to create a weapon that could protect her forest against undead invaders.
• At some point, Xanthoria’s research became more geared toward creating a ward against death itself, then finally toward achieving lichdom.
• According to the book, Xanthoria never discovered the source of the undead incursion that prompted her initial research.

Zelyth doesn’t know what caused Xanthoria’s slide into madness. If questioned about the saprophytic plague, Zelyth muses that the book’s information could be helpful in preventing further outbreaks.

Zelyth allows the characters to spend as much time with the book as they need. When they’re done with it, Zelyth returns the book to its vault.

Book Description

The book’s browned pages have become swollen and wrinkled due to age and exposure to moisture. Crumbling yellow lichen obscures the title on the front cover, rendering it illegible. Harmless spores puff into the air when the book is opened. Standing eight and a half inches tall and five inches wide, it has been cataloged as Xanthoria, titled after the author who is identified inside the work.

Joining of Two Worlds

Written in Common, Xanthoria begins with a set of scientific essays about symbiotic relationships in nature before deteriorating into confusing ramblings on the merits and similarities of life and death. It describes the author’s numerous experiments both natural and unnatural. One of the more thorough studies details the life cycle of a worm-like parasite that infiltrates different species of wasps, taking over their motor functions, while essentially wearing their still-living bodies as a disguise so the parasites can infect other wasps.

Ultimately, Xanthoria found a way to link her soul to the life force of another creature and thereby unnaturally prolong her own life, by transforming the other creature into a phylactery.

Characters who peruse Xanthoria learn the following additional information:

• Xanthoria was fearful of a surge in undead invading the forest near her home in the Lykortha Expanse, a cave complex. She was seeking a way to stop their spread and preserve what she viewed as the natural order of things.
• Most of the book discusses healthy symbiotic relationships in nature.
• The author spent time researching undead in the hope of gaining insight into their actions and ascertaining where they could be coming from.
• As the author sinks into madness, the writing turns into almost incomprehensible fragments, many alluding to her desire to combine natural life and the undead.
• The end of the book records several failed attempts by Xanthoria to extend her life through a process similar to becoming a lich. There are various drawings of dissected animals and humanoids alongside musings on the viability of experimenting on fey creatures.
• The sketches and margin notes get progressively darker the farther one reads. The terms “Mycorji? Shedaklah?” and “Lady of Lichen” appear several times each. Furthermore, the number 222 appears frequently throughout the latter half of the book devoid of explanation.

Characters can locate the forest containing the Lykortha Expanse on a map. If one or more characters try to draw some conclusion about the outbreak based on the forest’s location, a successful DC 20 Wisdom (Insight) check allows them to safely conclude that the plague likely originated there.

Zelyth doesn’t know the meaning of the words “Mycorji” or “Shedaklah,” nor does she know the significance of the number 222. If the characters have experience fighting demons or knowledge pertaining to the Abyss, you can allow them to make an Intelligence (Arcana) check. On a check total of 20 of higher, a character recalls that the Abyss’s 222nd layer is known as Shedaklah and sometimes is called Mycorji. On a total of 25 or higher, the character also knows that this layer is home to two demon lords: Juiblex, the Demon Prince of Oozes, and Zuggtmoy, the Demon Queen of Fungi.

The Lykortha Expanse

Characters can use the notes in Xanthoria to locate the Lykortha Expanse and the forest surrounding it. This natural cave complex was created by eons of erosion and hosts a wide array of lichen, molds, and fungi—an ideal location for Xanthoria’s research. Though she worked to make it suitable for habitation, it has fallen into an unhealthy state and reflects the druid’s deepening insanity.

General Features

The areas that make up the Lykortha Expanse have several common physical features, summarized here:

• Light. The complex is dimly lit by bioluminescent fungi growing in patches on the walls.
• Fungus. The ceilings, walls, and floors are coated in fungal growth.
• Passages. The caves and tunnels are made of unworked stone. Ceilings throughout are 20 feet high unless otherwise noted.

Madness of Zuggtmoy

Certain effects within the Lykortha Expanse can afflict characters with a type of madness brought on by the influence of Zuggtmoy. A greater restoration spell or more powerful magic rids a character of this madness, which otherwise lasts until cured. The madness gives the character a new flaw that suppresses any contradictory character trait. Roll on the Madness of Zuggtmoy table to determine the flaw.

Madness of Zuggtmoy

Encounter Locations

The following locations are keyed to the map of the Lykortha Expanse.

L1. Entrance

Ahead, a darkened cave mouth beckons from beneath the forest canopy. Growths of green, brown, and gray lichen cover the cave mouth, and a small stream flows deeper into the yawning darkness.

The character who has the highest passive Wisdom (Perception) score hears faint crying coming from a small stand of stones. Investigating the cries reveals a tiny winged figure, head in hands. This is Thunderwing, a sprite. She immediately gravitates toward characters who are friendly toward her.

Thunderwing looks mournfully at the adventurers and snuffles loudly, bubbles of snot forming beneath her tiny nose. If someone is kind to her, she tells them the following:

• She used to live here with her friends, Xanthoria and Bunny Blossom. Xanthoria is a druid of Silvanus, and Bunny Blossom is a yellow faerie dragon.
• Xanthoria subjected her to some terrible experiment. It hurt badly, but she managed to escape somehow. She flitted about in the darkness until reaching the cave mouth. She’s been sitting here feeling sad and missing Bunny Blossom ever since.
• Thunderwing has no sense of direction and no sense of time. Any questions relating to such topics just confuse her.

The first character who touches Thunderwing experiences an image in their mind’s eye of a female half-elf in a gossamer cape made of mycelial threads. This brief vision is accompanied by a momentary feeling of intense longing and hunger. This event occurs only once.

Thunderwing was Xanthoria’s friend until the druid’s mind became twisted by the influence of Zuggtmoy, causing Xanthoria to conduct grisly experiments on living creatures. Thunderwing is one of Xanthoria’s more recent subjects. The sprite looks alive, yet she is subject to effects that turn undead.

Thunderwing can’t be harmed unless she chooses to be. This is true for as long as she functions as a living phylactery for Xanthoria. Weapons and harmful effects pass through her as though she were a mere projection.

Thunderwing accompanies the characters as they explore the Lykortha Expanse, providing additional information she “remembers” if they need clues. The sprite can’t remember if Xanthoria is home or not, but she doesn’t recall seeing the druid outside the cave complex recently. Since Xanthoria moves freely throughout the Lykortha Expanse, she could be anywhere, according to Thunderwing.

Personality Trait

“I’m very emotional.”

Ideal

“Living things should be free and wild, not caught up in the trappings of civilization.”

Bond

“I will always try to help a friend.”

Flaw

“I’m such a scatterbrain. I forget important pieces of information until something reminds me.”

L2. Alchemist’s Alcove

Spiderwebs and mold cover everything inside this room. A rotting wood table and a set of shelves stand along the far wall. Glass jars, a mortar and pestle, and various other alchemical supplies lie scattered about the space.

Treasure

Though most of the bottles in this room have been ruined, a few are in fairly good shape. A thorough search yields a Potion of Superior Healing and a mildewed notebook containing instructions for concocting a potion of longevity out of fungi and a pint of blood from an archfey, all harvested within the past 24 hours. The handwriting in this notebook matches the handwriting in Xanthoria.

The potion-brewing ritual described in the notebook requires alchemist’s supplies and the aforementioned ingredients. The ritual takes 1 hour to perform, at the end of which the brewer makes a DC 30 Intelligence (Arcana) check. On a successful check, a potion of longevity is created. On a failed check, the potion is created but loses its potency after 10 minutes; on a check that fails by 5 or more, the brewer also ages 4d10 years.

L3. Cavern of Souls

Stalks of slimy, violet mushrooms as tall as a person dot this cavern. Mycelial tendrils drift from the domed roof of the cavern, softly pulsing with a mauve glow. Two humanoid figures lie suspended in the strands ten feet above the cavern floor, their flesh intertwined with the oozing tendrils.

This cavern was created by Xanthoria to conduct more experiments as she descended deeper into madness. Specifically, Xanthoria found herself able to communicate with other beings that had been infected with her spores and wanted to understand the process further.

Suspended Subjects

The two beings suspended in the mycelium were a human named Konrad and an orc named Rugga Two-Guts. Now they are fused with the fungus and constitute something else entirely. Both Konrad and Rugga are in constant agony. They can communicate telepathically out to a range of 60 feet. Their communications consist of pleas to release them from their torment. This can be accomplished by cutting both creatures free of the mycelium or by destroying the mycelium that holds them. Either accomplishment spells their doom.

A character with a knife or other small blade can use an action to try to cut a subject free of the mycelium, doing so with a successful DC 20 Strength (Athletics) check. On a failed check, the character takes 20 (4d8) necrotic damage and disturbs the mycelium; roll a d6 and refer to the Mycelium Effects table. Fungus creatures and those that have been infected with saprophytic plague are immune to these effects and are not targeted by them.

Mycelial Threats

Three of Xanthoria’s fungal servants lurk in this room, each indistinguishable from one of the mushroom stalks. The fungal servants try to destroy intruders. For one fungal servant, use the mummy lord stat block, but omit its lair actions and regional effects, and replace its sand-based effects with spore-based ones that are functionally identical. Use the vrock stat block for the other two.

Attacking the Mycelium

If the party is inclined to destroy the mycelium, treat it as a Huge object with AC 16, 300 hit points, a damage threshold of 10, and immunity to acid and poison damage. Every time the mycelium takes damage, a random effect occurs as determined by rolling on the Mycelium Effects table.

Mycelium Effects

If the mycelium is destroyed, the room is engulfed in a psychic backlash. Those present receive visions of an endless forest of tower-sized mushrooms, a woman wearing a holy symbol of Sylvanus running between them crying gooey, ochre tears, and a skull-splitting cry of anguish. Each creature in the cavern must succeed on a DC 16 Wisdom saving throw or take 44 (8d10) psychic damage. Thunderwing is immune to these visions.

L4. Moldy Bedroom

An unlocked wooden door seals off this cave.

This cave reeks of mold and mildew. Delicate white vines with brilliant purple flowers drape portions of the walls and floor. A large straw pallet in disrepair sits in the far corner with a broken oak table next to it.

This room was Xanthoria’s sleeping chamber, though once she completed her transformation into a lichen lich, she had no more need of it. At the back of the cave lurks a strange bundle of white poison ivy with a single bulbous eye in the center (use the death tyrant stat block, but omit its lair actions and regional effects). In the middle of the room, a mold-encrusted skeleton jerkily rises, wearing armor made of calcified lichen and covered in fungal growths (use the death knight stat block).

White Vines

If one or more characters enter this cave, the white vines clinging to the walls quiver as the purple flowers open wide and spread their sweet scent. Each character in the cave must succeed on a DC 18 Constitution saving throw or fall unconscious. Characters who are immune to any effect that would put them to sleep succeed on the saving throw automatically. An unconscious character is restrained by the vines and takes 66 (12d10) piercing damage at the start of each of its turns until it is no longer restrained in this way.

Characters can kill the vines by attacking their root in the center of the room. Treat the root as an immobile, Medium object with AC 15 and 100 hit points. When the root is reduced to 0 hit points, the vines release spores into the air as they die. These spores attach themselves to all creatures in the cave and have no effect until those covered with them face off against Xanthoria (see area area L11). Those who are exposed to the spores but take the time to wash themselves off with water suffer no ill effects.

Development

If the characters are having trouble understanding the path that Xanthoria now walks, this is a good point to have Thunderwing remember being subjected to an experiment like one described in Xanthoria.

L5. Faerie Ring

In the center of this oval cave stands a ring of brightly colored mushrooms ranging from three to eight feet tall. The air smells heavily of mildew.

The mushroom ring in the center of the room is a fey crossing. It was through this gateway that Thunderwing and Bunny Blossom first arrived, though the ring was not contaminated at that point in time.

The ring in its corrupted state makes Thunderwing feel ill, and she turns away from it in sadness. Thunderwing warns those near the ring to stay away from it, saying that something is wrong with it and it doesn’t lead to home anymore. Anyone who ignores her warning and steps into the ring to try to use it sees an image that only they experience:

The cave disappears and is replaced by a field carpeted in spongy moss and pockmarked with pools of ooze. A colossal palace constructed of giant mushrooms with interconnecting bridges rises in the distance. A cloud of spores falls gently from the sky, covering everything in a fine layer of the substance.

A tall creature beckons with a smile. Her body’s top half vaguely resembles that of a humanoid. Four ropy, fibrous antennae grow from her forehead, somehow enhancing her disgusting and compelling beauty. Her lower half is a mass of writhing, pulsing tentacles covered with fungal growths, resembling a horrific gown.

The figure in the vision is Zuggtmoy, with her fungal palace in the background. Anyone who experiences the vision becomes afflicted with the madness of Zuggtmoy (see “area Madness of Zuggtmoy” earlier in the adventure).

The vision is fleeting, and characters who experience it find themselves back inside the faerie ring when it concludes.

L6. Flooded Cavern

A huge pool of stagnant water fills this cave. Blooms of glowing green algae drift on the surface while tiny, white bioluminescent fish flit around in the water.

The water has a layer of algae that thickens at one end of the pool, and on the other end tiny bubbles rise from an underground spring that slowly flows into the pool. Tiny fish swim under the algae, occasionally surfacing to eat water bugs.

Drinking the water or bathing in it causes no ill effects. A character who succeeds on a DC 16 Wisdom (Perception) check finds the image of an oak leaf—the symbol of Silvanus—etched on one of the walls. This is a safe room to rest in.

L7. Kitchen

An unlocked wooden door seals off this cave. The door is covered with what is obviously a patch of yellow mold (see “Yellow Mold” in the Dungeon Master’s Guide). Any intruder who opens or otherwise disturbs the door causes the mold to release its spores.

The stonework in this cavern suggests this area was once a kitchen. Pots and pans lie piled on the floor in one corner, as if someone had started to gather them. Kitchen utensils are scattered about the floor, most of them bent and misshapen. Open bags of spices rest on shelves, and rat droppings are evident on every surface.

The pots and pans are rusted, and many have broken handles. A bent utensil breaks if someone tries to repair it, and the bits of spices and other ingredients here and there in the room have infestations of mold and insects. Thunderwing looks forlornly about the kitchen and cries a bit, lamenting the loss of the Xanthoria she remembers.

Lost Memento

Searching the room uncovers a recipe book wrapped in oilcloth under a pile of refuse. A successful DC 15 Intelligence (Investigation) check reveals that the handwriting closely resembles the older writings of Xanthoria. A preserved oak leaf serves as a bookmark, and sketches of Thunderwing and Bunny Blossom are drawn in the margins. See area area L11 for more information on how seeing this book affects Xanthoria.

L8. Meditation Cavern

An unlocked wooden door seals off this cave.

The air hangs heavy and rotten in this terraced cavern. Patches of brilliantly colored mushrooms dot the upper terrace, in the middle of which is a narrow stone staircase leading down to a roughly hemispherical lower chamber. The walls of the lower area sport murals of animals and fey creatures depicted in fungal reliefs.

This is Xanthoria’s space for meditation and relaxation. The murals covering the lower chamber’s walls are truly disturbing; their colors, textures, and patterns are nauseating to behold. Any character who takes the time to study the murals and succeeds on a DC 20 Intelligence (Religion) check uncovers subtle symbology related to the worship of Zuggtmoy. A character who succeeds on this check must then succeed on a DC 16 Charisma saving throw or become afflicted with the madness of Zuggtmoy (see “area Madness of Zuggtmoy” earlier in the adventure).

A search of the cave yields a bundle of parchment detailing research on Shedaklah, the 222nd layer of the Abyss. A fetid wasteland of fungus and oozes, this is the seat of Zuggtmoy’s power.

L9. Cove of Experimentation

Thunderwing trembles in fear upon reaching this area. She can’t remember why this particular location frightens her, and convincing her to enter the cave requires some gentle coaxing.

The stench of rot pervades the air in this cavern. Several stone tables covered in suspicious-looking red stains stand amid several rusty cages. A two-foot-deep coating of gray fog blankets the floor, and two huge, reptilian creatures with twelve legs apiece crawl across the damp ceiling.

The creatures crawling across the ceiling are two Behir. When they roar or discharge their lightning breath, thousands of gray, parasitic blood worms can be seen writhing inside their mouths.

Any creature swallowed by a parasite-infested behir must succeed on a DC 19 Constitution saving throw at the start of each of the behir’s turns or be feasted upon by blood parasites, taking 36 (8d8) necrotic damage on a failed save, or half as much damage on a successful one. (This damage is in addition to the damage caused by the behir’s digestive acids.) Targeting the behir with magic that removes a disease kills off its blood parasites.

Fog

The fog is confined to this chamber and covers the floor here to a depth of 2 feet. Any creature or object completely submerged in the fog is heavily obscured.

The behirs avoid the fog by crawling along the walls and ceiling. When a creature enters the fog for the first time on a turn or starts its turn there, it must succeed on a DC 16 Constitution saving throw or gain 1 level of exhaustion. A creature that makes a successful saving throw against the fog becomes immune to it for the next 24 hours (although levels of exhaustion already gained aren’t removed).

If Thunderwing sees one or more party members struggling with the effects of the fog, she overcomes her fear of the cave and flits around it while avoiding contact with the fog. Pulsing with arcane power, she blows the fog away before collapsing. She recovers after 1 minute with only a hazy memory of what she did. A gust of wind spell or similar magic also disperses the fog, which returns after 10 minutes.

Cages

The cages contain some of Xanthoria’s failed experiments, which she left to die and rot:

• The rotting corpse of what looks like a displacer beast, but one with far too many tentacles and limbs.
• The yellowed skeleton of a tiny dragon with a second head, all its flesh rotted away. Its body is curled up in an unnatural position, and its wings are outstretched oddly as if it were suffering some unknown agony. These are the remains of the yellow faerie dragon Bunny Blossom.
• The skeletal remains of a sprite dressed in brightly colored but tattered clothing. Its translucent wings are shriveled and crumble at the lightest touch.
• The rotting and mutilated remains of four goblins and two wood elves.

Development

Anyone who touches Bunny Blossom’s corpse is filled with a kaleidoscope of visions: a feverish half-elf with long blonde hair (Xanthoria), Thunderwing screaming at the center of a runic circle, and the two staring into each other’s eyes.

Treasure

Once the undead behirs are dealt with, characters who search the cave thoroughly find Xanthoria’s staff of the woodlands leaning against a wall in the eastern alcove. The staff is fully charged.

L10. Charnel Pit

The stench of death is thick in this yawning cavern. The floor slopes toward a hole rimmed with corpses and oozing fungi. Amputated pieces from a variety of creatures hang from the walls and ceiling in this hideous space.

This is where Xanthoria disposes of failed experiments or anything else she dislikes. The pit is inhabited by a purple worm bound to Xanthoria’s will. The worm consumes anything thrown into the hole.

As the Worm Turns. Once the characters enter the chamber, the worm rumbles forth and tries to devour everyone. At the end of each character’s turn, roll a d4 and consult the Charnel Worm Effects table to see what additional danger the party faces from the worm.

Charnel Worm Effects

Treasure

Lodged in the purple worm’s gullet is an emerald the size of a halfling’s head (worth 25,000 gp). Once the worm is dead, a search of its gullet yields the enormous gemstone.

L11. Xanthoria’s Grove of Horrors

An unlocked wooden door seals off this cave. The door is covered with what is obviously a patch of brown mold (see “Brown Mold” in the Dungeon Master’s Guide). Any intruder who opens or otherwise disturbs the door causes the mold to release its spores.

The scent of decomposing vegetation is overpowering in this area. Creatures of all shapes and sizes are partially entombed in fungal growths resembling a horrifying botanical garden. Ancient mushrooms as large as trees loom overhead, and puddles of stinking goo dot the floor.

The spores from area area L4 have fully incubated by the time the characters reach this location. Any creature that was exposed to the spores and did not wash them off is now subject to their full effect. At the start of its first turn after arriving here, the creature must make a DC 20 Constitution saving throw, taking 50 necrotic damage on a failed save, or half as much damage on a successful one.

When the characters reach the north end of the grove, read:

The tunnel leads to a dead-end cave supported by a natural pillar of rock. The chamber contains a riot of fungi and tree-sized mushrooms, as well as more puddles of ooze.

Under one of the giant mushrooms, a robed figure works furiously on a vivisected deer splayed across a moss-covered table. Ten feet away, a young boy bounces excitedly in an iron cage, swinging it to get a better view of what the robed figure is working on. He is not afraid but seems curious, and he is clean and seems well fed. He addresses the robed figure, calling her Xanthoria and asking her to show him what she’s doing in an attempt to alleviate his boredom.

Xanthoria, a lichen lich (see her stat block at area the end of the adventure), senses the characters and shoots them a crooked smile. As she does so, the boy’s form abruptly stiffens and his body withers into a dry husk. Stealing the life force of the boy enables her to cast antilife shell immediately and without visibly doing so. She continues to concentrate on the spell as she resumes her grisly work.

Xanthoria was a half-elf druid of Silvanus, and a small symbol of Silvanus hangs around her neck. Unfortunately for her, she fell into madness and her research became twisted due to the machinations of Zuggtmoy. She began to perform terrible experiments on living creatures to try to find ways to bridge the gap between life and death. Eventually, she turned her experiments on herself, causing her to transform into an unholy lichen lich.

Xanthoria is quite lonely and willing to talk to the group that has entered her grove, though she cannot be persuaded to discontinue her experiments. She has been aware of the characters' presence since they first entered the ruins of Lykortha and has been eagerly awaiting their arrival.

Xanthoria should be well prepared for the adventurers by the time they arrive at her warped druid grove and laboratory. She has called a nalfeshnee named Danjak to her service. Danjak is an emissary of Zuggtmoy, and the demon’s form is crusted and interwoven with a riotous blend of molds, lichen, and fungi. He lurks at the back of the cave, awaiting Xanthoria’s command before stepping out of the shadows. Additionally, nearby lurks the rotting husk of an infected treant ready to defend its master. The treant can’t use its Animate Trees action here, since there are no other trees in the vicinity. In addition to the treant, four invisible Will-o'-Wisp flit about the grove, ready to use Consume Life on adventurers who fall in battle.

Environmental Factors

Xanthoria’s grove and the tunnel leading to it from area L9 are warded against magical travel by creatures other than Xanthoria. Such creatures can’t teleport into or out of this area or use planar travel to enter or leave it. Effects that allow teleportation or planar travel do function if the starting point and the destination are both within this area.

Lost Memento

Showing Xanthoria the book from area area L7 awakens long-dormant memories of her previous life and causes her to take no actions, legendary actions, or lair actions until the end of her next turn. The book affects Xanthoria in this way only once.

Xanthoria’s Defeat

Once Xanthoria is defeated, the characters find the last few pages of her notes among her possessions. They detail her growing obsession with undead and her success at turning Thunderwing into her phylactery.

Armed with the information about Xanthoria’s phylactery, the characters must convince Thunderwing to give up her life to destroy the lichen lich once and for all. Here are some of the ways in which the characters might convince Thunderwing to sacrifice herself for the greater good:

• Promising to raise her friend, Bunny Blossom the faerie dragon, from the dead.
• Promising to complete Xanthoria’s original mission to rid the surrounding forest of undead.
• Destroying Xanthoria’s notes so that the process of creating a lichen lich can never be duplicated by anyone else.

Convincing Thunderwing to give up her life should be handled through roleplaying rather than ability checks, although you can require the characters to succeed on a DC 15 Charisma (Persuasion) group check if the scene proves difficult to roleplay. If Thunderwing is convinced to sacrifice herself, she lets out a deep sigh before flying about and kissing each character on the forehead—even the ones she doesn’t like. Finally, she approaches the character with whom she has made the strongest connection, lies down in their open hands, and shivers slightly before expiring. Thunderwing can’t be brought back to life by any means.

If the adventurers fail to convince Thunderwing to give up her life, she turns invisible and leaves the cave complex, taking refuge in the surrounding forest. Xanthoria re-forms 1d10 days later, appearing next to Thunderwing. The rejuvenated lichen lich then relocates to another lair to resume her research as the plague continues to ravage Faerûn.

If the characters return to Candlekeep, they find Zelyth eager to hear the tale of their harrowing experience. If the characters inform Zelyth that Xanthoria has been destroyed, Zelyth thanks them for putting an end to Xanthoria’s madness and granting her the final rest that she deserves.

The destruction of Xanthoria and her phylactery halts the spread of the saprophytic plague. Creatures infected by the plague continue to suffer its effects but no longer utter the word “Xanthoria” as they lose their mycelial connection to the lichen lich. Moreover, their spores are no longer contagious.

Lichen Lich

Lichen Lich are the undead remnants of powerful druids.

A lichen lich looks like a skeleton covered with fungi and bark-like lichen. A lichen lich has vines writhing within its chest cavity. These vines exude viscid and poisonous black fluid.

Lair Actions

On initiative count 20 (losing initiative ties), the lichen lich can take a lair action to cause one of the following effects:

• Poisonous spores fill a 10-foot cube that the lich can see within 120 feet of it. Any creature that enters the cloud for the first time on a turn or starts its turn there must succeed on a DC 19 Constitution saving throw or be poisoned until the end of its next turn. The cloud lasts for 1 minute or until it is dispersed by a strong wind.
• The lich commands the might of its diseased grove, creating a shambling mound. The shambling mound appears in an unoccupied space within 30 feet of the lich, acts on its own initiative count, and obeys the lich’s commands. The shambling mound dies after 1 hour or when the lich uses this lair action again.
• Rotten roots and vines magically erupt in a 20-foot radius centered on a point on the ground that the lich can see within 120 feet of it. the lich is unaffected by the roots and vines. For all other creatures, the area becomes difficult terrain, and each creature in the area must succeed on a DC 19 Strength saving throw or be restrained by the roots. As an action, a creature can try to free itself or another creature within its reach, doing so with a successful DC 19 Strength (Athletics) check. The roots and vines wilt away when the lich uses this lair action again or when the lich dies.