Dart plants are mobile plant creatures that appear in a wide variety of shapes and sizes. Those who’ve stopped to dissect the dead ones claim to have found complete animal skeletons deep beneath these masses of bark and vine, suggesting a parasitic nature.
Colorful flowers grow at irregular intervals on the dart plant’s surface, in which they form tight clusters of dart-like thorns, each carrying thousands of microscopic spores. When the cluster is ready, the flower closes, forming an airtight tube that acts as a blowgun.
As the spores travel through the host creature’s bloodstream, they multiply and feed on the nutrients intended for the host’s own organs. Treat this as a disease that slowly drains the constitution of host creatures and eventually kills them, at which point the dart plants consume the corpse from the inside out.
This constitution drain occurs at a rate of one point every six hours (or one HP per HD, if it’s a monster and you’re playing an OSR game). PCs and important NPCs are entitled to a saving throw vs. poison at each interval to temporarily avoid the effect, but the infection continues.
If a creature is still alive after a week of this, its immune system naturally kills off the infection. Cure disease spells and potions remove the infection as normal, but they don’t restore the victim’s constitution score to its previous level. Survivors of dart plant infection can be identified by their unnaturally pale skin, scales, fur, or feathers.
Mature dart plants are just a little bit bigger than their host creatures were. They have the same number of hit dice (including character levels) and can move at half the original creature’s speed. Each dart plant only has so many clusters ready to fire at any given time, but they also have a slam attack that does damage dependent on the size of the dart plant. The number of readied dart clusters is also dependent on the size of the plant, and uses the same table the slam attack does.
small: 1d4
medium: 1d6
large: 2d6
huge: 3d6
gargantuan: 4d6
When the dart plant eats the brain of its victim, it also absorbs the creature’s memories and intelligence. Dart plants that grow out of sentient beings try to use this ability to gain the trust of the victims’ friends and companions. Even with less intelligent animals, this usually at least tells the dart plant where to look for more host creatures. The host creature’s personality has never been known to overpower the instincts of the plant itself.
One major limiting factor on the dart plant population is their high calorie intake. These plants’ unusually active lifestyle requires that they consume twice their own weight in animal matter per day or face starvation. Since their first dart clusters take a couple of weeks to form, many dart plants starve to death before they ever get a chance to procreate.
This meat is stored in whatever space is made reasonable by the animal’s anatomy — in most vertebrates, this would be the stomach and chest cavities. An internal root system digests the dart plant’s prey while the plant retains its ability to move around (provided that its prey is at least one size category smaller than it is). What this means to you is that if this area were to be sliced open from below, piles of bloody half-rotten body parts would come tumbling out like it was a piƱata at a GWAR show.
Any flowers that still contain readied dart clusters can be distilled into a potent drug that causes intense hallucinations. The drug can be imbibed like a potion, or administered intravenously by applying it as a poison to an edged or piercing weapon. The affected individual must save vs. poison or hallucinate for two hours (if the imbiber is willing, no save is necessary), during which they are not in control of their actions. Roll 1d12 every half hour until the end of the effect to determine the nature of the hallucinations and the actions of the affected creature. After the hallucinations end, the character will feel nauseous and generally not up to adventuring, and every roll they make during the next six hours suffers from disadvantage or a -2 penalty or whatever, while attacks against the character are made with advantage or a +2 bonus.
1. You are one with the intertwining root systems below you, granting knowledge of a hidden location.
2. Everyone around you is delicious meat and you are carnivorous and hungry so so hungry.
3. You are a talking tree and will not willingly allow yourself to be moved, screaming if overpowered.
4. Decay is nutrition. You must seek and devour any decaying flesh, plant matter, or feces you can find.
5. You are a leaf on the wind. Wander aimlessly, fleeing from anything that tries to touch you.
6. The sun is life. Fight your way to the nearest direct sunlight and fight some more to stay there.
7. Everything is fractals. Stand in open-mouthed bewilderment, allow self to be led by hand.
8. You are a thistle bush and everyone is a goat. You have legs for some reason and need to get away right now.
9. Find some insects (there are always some insects and many of the ones on Exodus are dangerous) and rub them all over your genitals.
10. You are a fruit (hurr hurr shut up) that must find an animal to eat you so it can spread your seed when it shits.
11. Shit, termites. Madly clawing at yourself does 1d4 hp per turn unless you’re successfully restrained.
12. Something’s wrong with this dose. Begin the slow transformation into a dart plant as if shot by one.
The drug is incredibly dangerous and hardly ever any fun at all. However, the potential reward is legendary. Dart plant venom is commonly available in any place where adventurers gather, but usually not allowed to be taken there or anywhere other place where the recipient would pose a danger to the public. The venom’s desirability stems from tales of friends of friends who took it and experienced visions of fantastic treasures, the locations and some of the nature of which these brave fools awoke knowing.
In game terms, this means that if a player on dart plant venom rolls a 1 at any point during this horrible trip,* they must write down three elements of the location they saw. Everything else is up to you to fill in with whatever the hell you feel like, but the three statements the PC wrote down are 100% true. If a PC rolls a one more than once,** If multiple PCs are tripping together and both gain secret knowledge, they learn of different locations.
This shouldn’t exactly be a Monkey’s Paw scenario, where there’s no real benefit at all, because you want the PCs to actually try it at some point. Still, the temptation is too strong to not give in at least a little bit. Pick one statement out of every three; you still have to follow the letter of the law but it leaves out something important and dangerous. If a magic sword is demanded, you could decide that it’s cursed. If the players state that there aren’t any traps in the dungeon, you could make the entire dungeon a trap and turn escaping from it into a puzzle.
*There’s a 1/3 chance of this occurring, if you’re curious.
**1/9 chance. There’s a 1/81 chance of someone getting to make nine demands about the same place, which is less than 2%.