Brainstorming Undead Plants

[Scalenex]

So I want to add some razzmatazz to my undead encounters. Also, I am running a thematic dungeon where the PCs need to cleanse several desecrated temples to each of the major gods and I figure undead plants would be a good mini-boss guarding the temple of the plant god.

I figure thematically, undead plants would photosynthesize darkness and draw nutrition away from animals.

A plant creature that is undead would not be that different from any other corporeal undead that attacks the living. They would just attack with thorns and toxins instead of claws and teeth.

I figure non-animate plants that are undead would provide a constant passive de-buff to the living nearby and/or a buff to nearby undead.

Logically, undead plants would "fight" with normal plants for soil and space. Maybe a non-mobile necromancer would act as a "farmer" to undead plants, but 99% of people would try to burn or chop down any undead plant in their area.


The hard part is finding the sweet spot, power wise. I don't want undead plants to be so powerful that they would logically overtake all plant life on the planet and by extension, starve out all animal life. I also don't want them to be so weak that they would be totally eradicated.

[sktarq]

Well my first thoughts are

why not make them powerful but have a very difficult time reproducing? That way they are good challenges but not likely to dominate the world. So unless rather odd circumstances are in place they are limited. Would also allow a good singular challenge elsewhere. Think various cursed oaks or whatnot. And heck perhaps the spell that turns a regular tree to an undead tree is cheaper (lower level spell slot or lack of components needed) if it was involved in death somehow (hangman tree, body buried in its roots etc). So you'd have to focus on a list of what conditions would allow undead plants to start up or spread at all. Cursed regions, a necromantic area spell, certain numbers of classic undead corpses fertilizing/killing a plant that becomes undead on its own death, being hit by a death ray spell that missed, the grass that dead body was on when the raise dead spell failed or the dark channeling energy leaked from the corpse of some sacrificial victim....etc etc. Because really are these things natural? most of the time the undead are not. Also the purifying power of fire....the normal plants grow back the undead ones don't

As for competition otherwise....Well classically the sun is anethma to undead so they probably aren't fans so I would suspect they like the understory. And unless mobile they would have to start wherever the living version of the plant was before its death.
So what would plants consume....either other plants (like undead people try to consume living people) or nothing (mummy's and skeletons don't tend to eat much)...In theory I figure an undead plant could be just fine rooted to a rock...it needs soil like a wight needs turnips. Now the plant may have needed soil before it was turned so I wouldn't expect that very often but if the soil washed away after the plant was turned that makes sense. Also they could be parasites to other plants as well. Something weird like an Albino Redwood or some funky mistletoe.

Also think about what the differences would be between deciduous, evergreen, and those types of plants that die back to a bulb during winter...if the plant can't grow (because undead) and dies back to a bulb before it dies totally then the undead form would presumably be what it was like at the time of death...a bulb. Which would make it a PITA as a debuff spell trap.

Hmmm... flowers....well unless the plant gets quickly killed and raised while it is in bloom...undead don't classic grow so...no flowers but rule of cool may kick in. And lots of good death flower symbols... lilies and poppies and so many more.

Also what happens when someone or something eats the undead plants...that bulb may not be our cup of tea but some starving gopher...or termites looking for a new home....Lots of things like dead wood...hell a huge % of trees and limbs in a healthy forest are dead and rotting...they provide nesting spaces for all sorts of animals...so what happens to a woodpecker or toucan that is incubated in and grows up surrounded by undead wood rather than just dead wood? What happens to termites or beetles that try to chow down?

Also what about incorporeal plants....shadows, ghost, or banshee (mandrakes or groaning limbs for the wails) type plants. That could be neat. Both wonderous and bapping ya with a debuff spell.

Also what can you do with undead plants....does the wood make good wand material? do the flowers of an undead rose or shadow oak gall provide the ink for spell scrolls, optional components for spells perhaps? or just wood that is termite free for 10k years because nothing can eat it? A perfect hut all made from formerly undead plant material, the thatch, the floor, the chairs, the straw mattress,....could be valuable stuff to the right buyer...could farm that...which could give a necromancer a place in society as a provider of eternal goods.

[Anymage]

Lots of threats could wind up apocalyptic if nobody does anything about them. It's just that pesky adventurers tend to take care of threats well before they build up that much momentum.

In the case of undead plants, the likeliest case is that enough negative energy in the soil causes plants to grow as undead similar to how a high enough negative energy concentration causes corpses to spontaneously arise into unlife. The plants would help anchor and feed the negative energy, so in theory the area would grow if ignored. Undead plants wouldn't compete well outside of their normal environment aside from helping the slow creeping expansion of their domain, so adventurers can come in to cleanse the area and fix the problem and it's all good.

[brian 333]

Why would undead plants propagate? They are far more likely to be created, as are mindless undead, than they are to be able to seed. (Even undead creatures cannot have babies, for example.)

I could see a Treant Necromancer going around animating trees, but undead plants that create undead plants of their neighbors?

An Aspen Grove might be composed of a single root system with a thousand trunks, giving the appearance of an undead forest, but this is more akin to all of the skeletons from a single battlefield being animated by a curse of godlike power.

I can also envision a region which has been cursed. The Druid Circle of the Silver Forest was destroyed by a vampire who wanted the forest for some reason. It animated one of the dead druids and was subsequently slain. Now a druid vampire wanders the forest preserving things exactly as they were, using twisted necromantic versions of druid magic which has resulted in a forest of undead plants ...

Skeleton Tree

The leaves have long ago fallen from this tree and the bark only remains in tattered scales hanging where branches connect to the trunk. The twisted grain of the remaining wood gives it the color of polished bone.

Among the branches and littered on the ground around the tree are the bones of small to large creatures, as if some carnivore has been dragging its prey into the tree for a very long time, possibly for generations. Occasionally, fresher corpses are stuck in the treetop decaying, their juices staining the branches within which they are lodged.

This once living tree is now animated by necromancy. It does not grow, but neither does it rot. It cannot move from the spot into which it is rooted. It exists with a single purpose: to kill.

Its animator may give it instructions as a skeleton or zombie at creation. This will not generally prevent it from attacking living things which come into its reach, but it may exclude an individual or a distinct group, such as, "Blue-robed bipeds who hold their hands up," or some such simple, clearly visible identification. An instruction to "Kill no wizards," would be inappropriate because the tree has no means of determining class or levels. If a tattoo or recognition signal is indicated, it must be obvious and visible, but no spell or magical effect can be stipulated because the tree cannot detect or perceive magic.

The size of the tree determines the number of targets it can attack in a single round. Multiple attacks on a single target are also possible. A Skeleton Tree, drawn onto a grid or hex map, may make one attack per perimeter square or hex. For example, a sapling which occupies seven hexes has a ring of six hexes around its trunk hex. It is capable of making six attacks per round.

The reach of a Skeleton Tree is calculated as one third of its radius, (round up,) with all adjacent squares targetable no matter how small the tree. The sapling above would be able to attack any of the twelve adjacent hexes; however, with each hex of the perimeter being allowed to attack only adjacent hexes, only two of the hexes could attack a single hex, with six of the possible target squares only reachable by a single attack.

(Each perimeter square or hex is the origin point of each potential attack, and the range must be calculated from that origin point.

Ex: a tree with a radius of six hexes has a reach of two. A character two hexes from this tree can be targeted by a maximum of three attacks. Even adjacent to the tree the target would be susceptible to only four attacks.)

Some genius player may decide that the safest place is inside the tree's radius. Note that while each attack must be administered from a perimeter hex or square of the tree, being within the perimeter actually increases the number of potential points from which attacks can originate.

While a tree may be capable of twenty or more attacks per round, rules for subsequent attacks apply. In 3rd Ed, for example, each subsequent attack receives a cumulative -5 to the attack roll. This applies to each individual target, so three individual attackers are attacked at full bonus, with the second attack on each reduced to -5, the third attack on each target is reduced to -10, etc.

Size matters! A Small or smaller tree has a radius of 1, and can inflict a maximum of 1d4 per hit with its single attack. A Medium tree has a radius no greater than 3 and inflicts 1d6 per attack. A large tree has a radius of 6 or less, and each attack inflicts 1d8. A huge tree has a radius of 9 or less and can inflict up to 1d10 damage per attack. A gargantuan tree has a radius of 12 or less and inflicts 1d12 per attack. A tree with a radius of 13 or more is Colossal and inflicts 2d8 damage per hit.

Hits for damage are bludgeoning or piercing attacks, (50/50 random each attack if the distinction matters, the tree cannot learn or adapt, so each attack is random.) The tree may also grapple. In any attack round the first attack may (25% chance,) be a grapple attack. Small trees have Str of 5, with each size category increase raising the ability score by 5. Large trees have a Strength of 15, and Gargantuan trees would have an Str of 25. (This also applies to the damage modifier of melee attacks.)

Killing a Skeleton Tree can be difficult. They are immune to Piercing Damage, and Bludgeoning Damage inflicts half damage.

They also have lots of hit points. For each square or hex which can attack, the tree has 1 hit die. This total HD is used to determine bonus to attacks as well as the total number of hit points in the trunk of the tree. However, each hex covered by the tree has 1d8 additional HP specific to that hex. Eliminating a perimeter space by inflicting more HP in damage than the space has allows the spaces behind it to be considered perimeter spaces, and while they do not contribute to the tree's monster level, they are allowed attacks as the original perimeter squares or spaces.

The Skeleton Tree can only be destroyed by inflicting damage to the trunk which exceeds its HP total. If the trunk is not severed at the base, the tree will regenerate 1hp/hour beginning with the trunk and thereafter filling in each square or hex of its canopy at the rate of 3 spaces per day. Negative energy, of course, increases this rate of recovery.

The tree cannot move from the place in which it is rooted, so turning will only cause it to pull its branches away from the perfomer of a successful Turn, acting as cornered undead typically do. A powerful enough priest could theoretically destroy an undead tree, though in most cases a really really powerful priest would be needed.

Fires inflict normal damage, but the tree is exceedingly difficult to light on fire. A fireball will undoubtedly inflict enough damage to eliminate all of the canopy spaces within its radius and inflict damage on the trunk, but it is not going to start a fire which consumes the tree. A Combust spell, however, is very likely to do so because it specifically is designed to ignite such materials. Lobbing oil or other forms of Molotov Cocktails may eventually succeed as well.


Potted bonsai can be humorous versions of this monster. (1 attack, 1d2 damage, 1HD, 1 ft reach, diminutive)

Taller, narrower trees such as cedar or pine may have reach of 1 space per 2 radius spaces, while broader, shorter trees such as live oak or fig may have reach of 1 space per four radius spaces.

Ironwood trees may have 10 or 20 DR while Balsa trees may have vulnerability to slashing attacks.

[sktarq]

Why would undead plants propagate? They are far more likely to be created, as are mindless undead, than they are to be able to seed. (Even undead creatures cannot have babies, for example.)

THe one image I get is spawn. So if you have something similar to a shadow or wraith oak tree...when it's roots touch those of another plant it starts sucking the life out of it and when it kills said other plant that plant becomes a wraith/shadow version of itself. They could have some form of ranged attack that could work in a similar manner (pollen for example) and again would be something that would need a living plant to work turn into the undead not grown from soil/scratch... so generally I agree but I could see how you could blur the line a smidge.

The main verb associated with plants is "grow" and undead don't do that. They don't grow the plant itself, they don't grow flowers, fruits, or seeds...there is a fundamental staticness that will make the concept a bit of threading the needle.

[brian 333]

Sawgrass Marsh

Damp trails wind through rotting trees hung with beards of moss and vines twined over, around, and through everything, creating nets and curtains which limit sight and channel movement. The trails lead to what appears to be an oxbow lake surrounded by bright green grass.

The grass is sawgrass, and its roots grow into mats which float over mud and rotten vegetation. These mats also grow over water, forming rafts which fish and amphibious creatures swim beneath. These mats give the illusion that the lake shore is far out in deeper water, and while they will support some weight, each step has a chance that the walker will break through into the mud and water beneath.

To make matters worse, tiny biting gnats swarm in the sawgrass leaving painful bites which cause severe itching welts that become infected when scratched.

To make matters even worse, the sawgrass itself gets its name from the serrated edges of the grass. While moving through the marsh, any exposed skin gets multiple shallow slices which, when combined with the sticky toxic sap which collects in the serrations, creates intensely burning cuts which attract swarms of the blood-sucking gnats.

And to make things even worser, existing in the marsh are tiny clumps of dead sawgrass animated by necromancy. These undead plants look like the hair from modern troll dolls, but they can move and whiplash their victims, causing the papercut-like lacerations. However, instead of sap, the undead sawgrass inflicts Negative Energy damage and with each successful hit forces a DC 16 save to avoid suffering a temporary loss of 1 point of STR ability. A victim with less than 3 STR cannot walk, and a victim with less than 1 point of STR cannot move at all.

An immobilized or slain victim will be dismembered by the Undead Sawgrass and the parts dragged away to be hidden in the living sawgrass. The clumps of grass they are hidden in die and consume the flesh, becoming Undead themselves. A Tiny creature has enough mass to create one clump of Undead Sawgrass. A Small creature can create two, 4 for a Medium sized victim, and 8 for a Large victim.

[Scalenex]

Well my first thoughts are

why not make them powerful but have a very difficult time reproducing? That way they are good challenges but not likely to dominate the world. So unless rather odd circumstances are in place they are limited. Would also allow a good singular challenge elsewhere. Think various cursed oaks or whatnot. And heck perhaps the spell that turns a regular tree to an undead tree is cheaper (lower level spell slot or lack of components needed) if it was involved in death somehow (hangman tree, body buried in its roots etc). So you'd have to focus on a list of what conditions would allow undead plants to start up or spread at all.

This is a very good idea.

Cursed regions, a necromantic area spell, certain numbers of classic undead corpses fertilizing/killing a plant that becomes undead on its own death, being hit by a death ray spell that missed, the grass that dead body was on when the raise dead spell failed or the dark channeling energy leaked from the corpse of some sacrificial victim....etc etc. Because really are these things natural? most of the time the undead are not. Also the purifying power of fire....the normal plants grow back the undead ones don't

This is a good idea, but it's not for me.

As for competition otherwise....Well classically the sun is anethma to undead so they probably aren't fans so I would suspect they like the understory. And unless mobile they would have to start wherever the living version of the plant was before its death.
So what would plants consume....either other plants (like undead people try to consume living people) or nothing (mummy's and skeletons don't tend to eat much)...In theory I figure an undead plant could be just fine rooted to a rock...it needs soil like a wight needs turnips.

Interesting. But my setting has very few undead that eat nothing, though I guess animated skeletons and zombies don't eat much and just take a small amount of ambient magical energy. Undead plants could be in the same boat.

Now the plant may have needed soil before it was turned so I wouldn't expect that very often but if the soil washed away after the plant was turned that makes sense. Also they could be parasites to other plants as well. Something weird like an Albino Redwood or some funky mistletoe.

Interesting, I had no idea albino redwoods worked liked that. And I used a picture of a albino redwood for something unrelated.
In fact I used it for something that is a weapon against the undead, Silverwood.

Also what happens when someone or something eats the undead plants...that bulb may not be our cup of tea but some starving gopher...or termites looking for a new home....Lots of things like dead wood...hell a huge % of trees and limbs in a healthy forest are dead and rotting...they provide nesting spaces for all sorts of animals...so what happens to a woodpecker or toucan that is incubated in and grows up surrounded by undead wood rather than just dead wood? What happens to termites or beetles that try to chow down?

Ghoulish termites is an interesting concept.

Also what about incorporeal plants....shadows, ghost, or banshee (mandrakes or groaning limbs for the wails) type plants. That could be neat. Both wonderous and bapping ya with a debuff spell.

That is a great idea.

Also what can you do with undead plants....does the wood make good wand material? do the flowers of an undead rose or shadow oak gall provide the ink for spell scrolls, optional components for spells perhaps? or just wood that is termite free for 10k years because nothing can eat it? A perfect hut all made from formerly undead plant material, the thatch, the floor, the chairs, the straw mattress,....could be valuable stuff to the right buyer...could farm that...which could give a necromancer a place in society as a provider of eternal goods.

Eternal goods is interesting. I was initially just thinking of undead plants being reagents (spell components) for necromantic spells but pest resistance wood is very clever.

Lots of threats could wind up apocalyptic if nobody does anything about them. It's just that pesky adventurers tend to take care of threats well before they build up that much momentum.

In the case of undead plants, the likeliest case is that enough negative energy in the soil causes plants to grow as undead similar to how a high enough negative energy concentration causes corpses to spontaneously arise into unlife. The plants would help anchor and feed the negative energy, so in theory the area would grow if ignored. Undead plants wouldn't compete well outside of their normal environment aside from helping the slow creeping expansion of their domain, so adventurers can come in to cleanse the area and fix the problem and it's all good.

Reasonable point.

Why would undead plants propagate? They are far more likely to be created, as are mindless undead, than they are to be able to seed. (Even undead creatures cannot have babies, for example.)

I could see a Treant Necromancer going around animating trees, but undead plants that create undead plants of their neighbors?

An Aspen Grove might be composed of a single root system with a thousand trunks, giving the appearance of an undead forest, but this is more akin to all of the skeletons from a single battlefield being animated by a curse of godlike power.

ay have 10 or 20 DR while Balsa trees may have vulnerability to slashing attacks.

SNIP

Your undead grove idea is very good. I'm likely to adapt it.

THe one image I get is spawn. So if you have something similar to a shadow or wraith oak tree...when it's roots touch those of another plant it starts sucking the life out of it and when it kills said other plant that plant becomes a wraith/shadow version of itself. They could have some form of ranged attack that could work in a similar manner (pollen for example) and again would be something that would need a living plant to work turn into the undead not grown from soil/scratch... so generally I agree but I could see how you could blur the line a smidge.

The main verb associated with plants is "grow" and undead don't do that. They don't grow the plant itself, they don't grow flowers, fruits, or seeds...there is a fundamental staticness that will make the concept a bit of threading the needle.

This would fall under an aforementioned apocalyptic threat because it destroy a continents forests if left unattended.

Sawgrass Marsh

Damp trails wind through rotting trees hung with beards of moss and vines twined over, around, and through everything, creating nets and curtains which limit sight and channel movement. The trails lead to what appears to be an oxbow lake surrounded by bright green grass.

The grass is sawgrass, and its roots grow into mats which float over mud and rotten vegetation. These mats also grow over water, forming rafts which fish and amphibious creatures swim beneath. These mats give the illusion that the lake shore is far out in deeper water, and while they will support some weight, each step has a chance that the walker will break through into the mud and water beneath.

To make matters worse, tiny biting gnats swarm in the sawgrass leaving painful bites which cause severe itching welts that become infected when scratched.

To make matters even worse, the sawgrass itself gets its name from the serrated edges of the grass. While moving through the marsh, any exposed skin gets multiple shallow slices which, when combined with the sticky toxic sap which collects in the serrations, creates intensely burning cuts which attract swarms of the blood-sucking gnats.

And to make things even worser, existing in the marsh are tiny clumps of dead sawgrass animated by necromancy. These undead plants look like the hair from modern troll dolls, but they can move and whiplash their victims, causing the papercut-like lacerations. However, instead of sap, the undead sawgrass inflicts Negative Energy damage and with each successful hit forces a DC 16 save to avoid suffering a temporary loss of 1 point of STR ability. A victim with less than 3 STR cannot walk, and a victim with less than 1 point of STR cannot move at all.

An immobilized or slain victim will be dismembered by the Undead Sawgrass and the parts dragged away to be hidden in the living sawgrass. The clumps of grass they are hidden in die and consume the flesh, becoming Undead themselves. A Tiny creature has enough mass to create one clump of Undead Sawgrass. A Small creature can create two, 4 for a Medium sized victim, and 8 for a Large victim.

Clever concept but not my cup of tea.

[brian 333]

Clever concept but not my cup of tea.

Sawgrass marshes are real, as are the gnats and the infected cuts. The undead clumps only seem real to those who must venture into the marsh.

Alligators, on the other hand, love it.

I would propose that the purpose of your adventure drive your selection of features for plant undead.

If you have an apocalyptic vision and your players must stop the progression or else, you do not have a lot of room for replayability. You could spend all winter creating the adventure background and mechanics, only to have a TPK three game sessions in. Bad guys win, let's start that Robots and Rocketships adventure Mel's been working on.

On the other hand, limiting the theme to a very specific adventure requires all of the effort to be discarded once that single adventure is completed.

So, somewhere in the middle seems about right to me. Create planties which can achieve undead status: treants, vegepygmies, whatever. They become clerics or druids of a vengeful but dead plant deity, (small audience!) And defeating a cult or cell would still allow the work to be reused in later adventures as these cultists spread out, creating mindless undead plants or weaker spawn as they go.

Example: The Circle Of The Silver Fir worshipped Duanatha-t'Nogh, a deity of intelligent plants, whose eight Treant druids organized the Valley in their worship and veneration.
Curse-ed dwarves came into the valley for lumber, and the plants of the valley resisted.

The dwarves clear cut, the plants resisted, and the dwarves managed to eventually kill the treant druids one by one. In desperation, the treants turned to undeath to revive their fallen comrades, not having time to grow new guardians. Although this did not prevent the dwarves from chopping down the Silver Fir, (the mortal avatar of Duanatha-t'Nogh,) it did kill the deity, who was raised to undeath by his undead druids.

The battlefield remains a huge area of treestumps with rotting vegetation covering the ground, but no new plants growing within. It is surrounded by a wall of dark trees which give viewers the impression they are being watched by beings of hate and malice.

Tunath-d'Nigh is now a deity of vengeance on those who harm planties. Wherever intelligent plants are persecuted there is a chance they can rise and become undead. Further, the priests of these creatures gain a portfolio of undead plant spells and feats. Turn Humanoid, for example, is a cleric feat available only to planties who worship this deity.


Pumpkins!

A drought or blight late in the season left a field of pumpkins to rot on the vines. But on the night of the Harvest Moon the withered vines begin to twitch and ravel themselves into grotesque mimicry of humanoid shapes. These vine-figures have at their center, or perched on top, rotten pumpkins which split into macabre faces which glow with an inner greenish or yellow light.

These pumpkin mannequins stalk towards the nearest dwellings with but one goal: to strangle the living, drag them into the fields, and bury them in shallow graves over which the pumpkins will scatter their seeds. Come morning, ploughed up fields of broken, rotted pumpkins and occasional blood-trails to the mounds over the graves are all that can be seen.

[brian 333]

The Black Woods

Once a prosperous village sat at the feet of a hilltop fortification. Ruled by the prestigious Rillain family for several generations, the village was a commercial hub for the surrounding farming communities. Misfortune set in, and rumors as to its cause ran rampant.

What is known is that Lord Aeobar Rillain died suddenly at the age of forty, and his grieving wife was sent to a nunnery until her grief was healed. The son Garford Rillain assumed lordship, and began his rule by imposing heavy taxes from his farmers in the form of lumber, building stone, and increased demands on crops.

Three druids of the Greenstone Glade came to him to teach him the harm he was doing to the lands he ruled, but he had them slain and their bodies were hung over the three roads entering into his lands. As the weeks went on, dark clouds massed over the land, crops blighted, and leaves fell from the trees.

His villagers began to desert, which he forbade, but the soldiers he sent to stop them also deserted. As the permanent clouds grew heavier and darker, sunlight failed to reach the ground. Winter set in, and the trees and other plants faded to either bone-white or to black. Ropy tendrils of black vines grew all along the fields and roads, shrouding and crushing houses. Any living thing they touched they killed, and dessicated corpses and skeletons were eventually devoured.

It is said that they crept up the keep of the manor, trapping Lord Rillain inside as they crept ever closer, until at last they trapped him in the highest room. Their tendrils merged into his body, trapping him inside a cage of magical unlife.

Over time the white trees covered in black leaves have overgrown the lands, and stunted black shrubs and grasses grow beneath their branches. Where once there was a prosperous land, now a shadow conceals plants which thrive in darkness, watered by the blood of the occasional fool who ventures down one of the three roads, beneath the mummified corpses of the dead druids.

It is said that undead creatures seek out the eternal darkness of the Black Woods, and that living people should not stray closer than a day walk from the edge.

It is also said that every strand of the black vines that grow throughout the forest is now a nerve that sends its perceptions back to the prisoner who still resides, unnaturally preserved, in the center of the Woods, eternally compelled to watch over the ruins of his ancestral lands.

DM Notes:
The vines are everywhere, and they passively inflict d3 Negative Energy Damage per round to whatever touches them. Spells and items which negate Negative Energy damage reduce or eliminate this environmental hazard.

Sunlight based spells destroy all plants in their area of effect. Creatures get normal saves versus these effects, though the undead plant template should include sunlight vulnerabilities.

DMs must populate the woods as suits them, but the writer recommends undead versions of plant-based monsters. Whether adventurers who die here become undead is likewise a DM choice. Undead which have HP restored by negative energy may be healed by the Negative Energy projected by the tendrils of the black vines.

Cutting down and burying one of the druids creates a zone around the grave where normal life may resume. In complete darkness this will be fungal life, but on the fringes of the clouds green plants that grow in dim light such as ferns will prosper.

Cutting down and burying all three druids will cause the persistent cloud cover to disperse. Each druid so treated reduces cloud cover by a third, but the full effect of this will not be evident for several weeks after each burial.

Destroying the Lord Rillain with sunlight will also cause the vines to wither throughout the region. Destroying him by other means will allow him to regenerate at 1hp/hour of darkness.

Undead plants and other creatures will continue to be a problem: their unlife is not connected to the woods, so they will continue to plague the region untill all of their hiding places are found.

[Vogie]

I like this idea - but I'd refine it into a certain direction. They're not just bizarro anti-plants that feed off darkness and the like, but they have a niche in the world, a reason to exist. So you have these undead seeds grow because they have a certain thing they're drawn to, and they only grow when those conditions are met.

The first thing that comes to mind is the moss that inhabits the Gloom in Sergei Lukyanenko's Watch series of novels. The gloom in that world is like a blend of the ethereal plane from D&D and the Upside Down from Stranger Things, and the moss inhibits the first layer - and it grows based on emotional and magical energy in an area. Because it's in a plane such as the ethereal plane, a normal person can't see it growing, only the magic-users ("Others" in the series) can. So that specific plant in the middle of nowhere away from people is completely inert and useless - but in the towns and cities, where people are meeting and clashing, arguing and falling in love, et cetera, the moss just runs rampant. And whenever the moss reaches a critical mass in a certain area, it starts shaping the area around it. A massive bloom of this moss will then start draining the emotions of people in the area, causing fatigue and exhaustion to spread, as well as turning them into kindling for explosive emotions (typically anger & rage) which of course fuels the moss even more. Shift such a plant into the material plane, and bam - you've got yourself an undead plant. Sprinkle in a type of magic camouflage so that the average adventurer can't see this moss growing all over this city, giving an astonishing reveal when one character sees through the illusion.

The myth of the mandrake from Shakespeare, which describes the plant as growing from the blood of hanged men, could instead be an actual undead plant that can only be watered by blood. A common trope in D&D-likes is a collection of creatures that follow each other around because they have a certain symbiosis - and in this case, Troglodytes are deadly creatures that are often followed by a flock of Stirges. They aren't annoyed by the smell of the troglodytes, and they love to drain blood from the destruction in their wake. An undead plant that grows from blood might be a type of the Redcap - a dangerous fey that resembles a gnome that spawns from pools of blood that have to coat their titular caps with more blood every so often or they'll wither away. Transforming that into a dangerous undead plant, maybe something like a carnivorous animated variety. There could then be a subsection of alchemy that is all about mixing the blood of supernatural creatures into a certain elixirs that can transform existing plants into a undead shell of themselves.

There's also a whole collection out there on how to turn certain types of magic into a passive area - namely, ghosts. A lot of the things that are currently used in ghostly or haunting tropes could then be tied into a sort of undead plant. Perhaps its a ghost that is implanted into seed or other type of plant by a mage, or perhaps this is something that occurs as a part of the normal supernatural ecosystem. One thing to look at is the Boneyard manifestation from the Geist: The Sin-Eaters book in the World/Chronicles of Darkness series. In that setting, all characters are people who had briefly died then came back with a ghostly passenger that imbues them with power. This could do things like weakening senses, causing things to age, imbuing feelings of claustrophobia or starvation, causing hallucinations or creating illusions, and causing existing plants and animals to act with animosity towards a target. When it comes to trees specifically, the corruption of nature spirits like dryads could be a reason that these things exist as well.

[Bohandas]

Undead plants would probably feed on other plants. Like be twisted into parasitic creepers even if they're a kind of plant that usually isn't.

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Also, maybe something like the plants in The Color out of Space where the fruits grow large and beautiful but are totally unnutritious and the insides look and taste like ash

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Also, how about vampire treants that are obsessed with maple syrup

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Has anybody here seen the bit in Evil Dead 1 where the girl gets attacked by haunted trees

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Or for that matter the various scenes in the Lord of the Rings novels with creepy trees. Like the willow that attacks the fellowship in the first book. Or the huorns from The Two Towers, the ents' spooky ill-tempered backup who nobody ever sees move but who nevertheless manage to surround and cut off the orc army

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What if the leaves and such actively sucked in light rather than passively collecting it, creating a darkness effect

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What about like the ghosts of trees that have died or been cut down just kind of chilling there being trees (at least until someone walks through one and possibly gets some kind of debuff)

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Or how about a pod people sort of thing where they passively drain the identities of people in the area as they sleep, eventually causing the victim to die and the plant to turn into a copy of the victim

[snusnumrik]

I imagine undead planets create darknessa round them. To protect from sunlight, which is deadly to them. This is the reason undead forests are gloomy and full of shadows.
An extract from a undead grass can be used to protect a vampire from the sunlight.