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Harpoon Cactus

"Sure I seen a harpoon cactus, same way anyone with sense looks at them, from a distance. If you can see the individual leaf mats you got to close, good luck or good riddance." - Jasper Cameron, Leader of The Bronze Ravens

Basic Information


The Harpoon Cactus has a very similar appearance to other members of the prickly pear family. It differs in 2 main ways. The first is that it has a large, long taproot in addition to its wide-ranging fibrous root system near the desert surface. This taproot does not to reach down to the water table, but is used to store water and "prime" the bio-hydraulic mechanism on which the harpoons operate.   The second is the tendency for mature plants to be surrounded on the ground by patches of leaves that appear both healthy and edible. These "leaf mats" mark areas where a victim has been claimed, and serve to lure prey into the unmarked ring of harpoons.   The working of the harpoon mechanism are actually quite fascinating. As the plant "dries out" the first thing that happens is the connective tissue of any extended harpoons contracts, drawing the harpoon back underground. Next, the harpoon chamber tightens around the harpoon, creating a rather effective water seal. Then, the fibers around the taproot chamber and water channels contract and tighten, pressurizing the mechanism. Lastly, the trip mechanism becomes rigid, arming the chamber. (Illustrations forthcoming)

Genetics and Reproduction

Like many members of the prickly pear family the Harpoon cactus can reproduce both sexually and asexually.   Sexual reproduction is through the pollination of its flowers. After pollination a sweet, bright blue fruit is formed. Seeds are dispersed by both birds and rodents that feed on these fruits.   Asexual reproduction is only possible during the regions infrequent lightning storms. In conditions when moisture is high it is possible for a pad that has been detached from the parent plant to take root and continue living. It is theorized that this allows a plant to "survive" lightning strikes.

Ecology and Habitats

The Harpoon cactus is only found in the Myrdhor Desert.
Wonderdraft step 4 (3).png

Dietary Needs and Habits

The harpoon cactus, often considered a carnivorus plant, is more accurately a hemovore, getting a vast majority of both the nutrients and moisture needed to survive from the blood of its victims. The actual poison used is unknown, but according to the experience of several scholars (all deceased) it is known to have paralytic and hallucinogenic properties, as well as acting as an "osmotic pump" forcing water in the victims body towards the area of penetration. The plant is also theorized to have properties similar to the foxglove family as a heart stimulant, as it was noted by the surviving apprentice of one of the above scholars that despite his master's apparent extreme dehydration he still had a strong, regular pulse for much longer than his outward appearance would have suggested.
"Do you know what it was like.... DO YOU?! I had to sit there just watching and recording, as Master András had asked. First came the short cries of pain, quickly interrupted. Then I watched as their bodies crumpled to the ground, eyes wide with fear, as I think out of all of us approaching the cactus it was assumed that at least one master would avoid the harpoons...   Next I watched as if weeks passed in mere hours. I watched their bodies dry out, more and more, until they looked like mummified remains or a zombie. I would have thought they were dead, but as they became more and more dehydrated it became clear, even from a yard or more away, that they all still had a steady and strong pulse. I am sure that they were still alive when the vultures and lyrebirds started in on them. I even got to watch as a brave jackal ate his last meal before falling victim to the neighboring cactus." - Hugo Kirsch, Former Apprentice to Master András.
    The bodies of the Harpoon cactus' victims are summarily disposed of by the various scavengers of the desert, many of whom have developed the ability to digest bone. This leaves the area around the cactus relatively free of remains.

Additional Information


While there is a Druid grove in the Myrhdor Desert that is protected by cactus fields, the Harpoon Cactus has yet to be successfully domesticated.

Uses, Products & Exploitation

The fruit can be harvested and eaten or used to make jam, mead, wine, or other fruit products.   Particularly skilled or incredibly foolish assassins have been known to try to harvest poison from the harpoon cactus, although whether any have succeeded is up for much debate.

Perception and Sensory Capabilities

Harpoon channels are pressure sensitive. The lower the water reservoir of the cactus, the more rigid the trip fibers become, and the lower the pressure required to trigger the harpoons release.

Civilization and Culture

Interspecies Relations and Assumptions

Pads and fruits are eaten by rodents, birds, and bats. Its flowers are also edible.   It also bears noting that the Harpoon Cacti share a close symbiotic relationship with the desert lyrebird. The lyrebird is capable of accurately mimicking the sounds of everything from the giant desert hauler-tortoises and elephants to jackals and hyenas, drawing unsuspecting creatures to their doom. Investigating cries for help with no apparent source has also been known to cause many a desert caravan to lose both guards and pack animals.   Indeed, the disappearance of famed Charred Brigade was attributed by its sole surviving scout to lyrebirds and the Harpoon Cactus.
cactus 2.png
Image from Smithsonian Open Access Library (Opuntia engelmannii Salm-Dyck ex Engelm.)
Scientific Name
Opuntia conus
Origin: Natural Evolution
Geographic Distribution

Sapphire Doldrum Mead

Should one be feeling exceptionally brave, incredibly lucky, or exceedingly desperate, the brewmasters of the Order of Half-Pints   will pay handsomely (3gp per fruit) for the fruit of the Harpoon Cactus in order to make their world famous Sapphire Doldrum Mead. This mead bears the same azure color often seen in calm equatorial waters. While the Half-Pints swear that there is no magic involved in its creation, it has an almost mystical calming effect which, along with its color gives the mead its name. For this reason it is often prized as the drink of choice for delicate trade negotiations and at peace talks.   That being said, it has been pointed out often by Brewmaster Bellowbell that while waters in the doldrums are usually known for being calm, they are also known for their sudden violent squalls.

The Last Retreat of the Charred Brigade

"We knew better. Knew... avoid the desert... but th.... th..... they were decimated, routed. We were *cough*... ordered to run.....*cough* survivors down. Twilight came, their forces just *cough* just out of reach all day. It..... it was dec... dec.... we would hunt them in the night *cough*. Used the... the usual c-c-calls to... signal... safe paths. Suddenly it sounded we had... *cough* twice the scouts w...we c..c...came with. The whoop of a crane, the call of a plains owl... led us ri...right into a c...c...cactus patch... shouts of "run" and "this way"" from every direction.... make no mistake we weren't defeated... army. The birds.... who knew.... learn..... so fast. Nearly 700.... men, gone... single night. The birds..."   -Unnamed scout of the The Charred Brigade , on his deathbed, Cause of death: dehydration and exposure.

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Cover image: by drunkenpanda951


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Eternal Sage AmélieIS
Amélie I. S. Debruyne
19 Mar, 2021 22:43

Great article! I love this idea of a carnivorous cactus, the biological details you've added, and your drawing is great! :D   I love that bit: "according to the experience of several scholars (all deceased)" XD   You said you're still working on it, so I have a few suggestions for you:   I wasn't familiar with the term "taproot", so maybe you could make a tooltip with the definition? Or add the term to your drawing.   Also when you says "The plant is also theorized to have properties similar to the foxglove family", you could add what those properties are as I'm not familiar with it. Even if I can deduced some of it from the example you give, I'd like it to be more explicit. Sae for "than his outward appearance would have suggested.", you can add a description of the appearance here. And some with your last paragraph. I can deduce that the victims who follow the cries of the bird get impaled on the cactus and then the birds feed on the corpse, but the information could also be directly given.   You could also populate your sidebar by adding a link to your map to show where you plant grows, and to put a list of "suggested articles" for people who want to continue reading in your world.   Also, would our desert look very different from those in your world? If not, you could add a stock photo of a desert.

27 Mar, 2021 16:59

Thank you so much for the feedback. I dont have very many articles that I can suggest, but I hope that the additions I provided at your suggestion flushed out the article a bit more.

23 Mar, 2021 21:18

This was a great read. The harpoon mechanism is something I have not seen before. Your cover image also has the feel of a real scientist's drawing encountering this cruel plant. :)   The quote section of the apprentice recording the death of his master was a good addition as well.   My main tip of improving the article further would be to either add new stuff to the sidebar section or removing it entirely since there is not a lot there yet. This could perhaps be filled with info of a related myth, culture or religion. Or perhaps the cactus can create some great alcohol beverage if people manage to get to it safely :p

Feel free to check out summer camp overviewif you want to see what I am up to!
27 Mar, 2021 16:59

Thank you for the feedback. Sapphire Doldrum Mead is now a thing due solely to this comment.

27 Mar, 2021 17:50

Oh so nice that it was added ! ^^ happy to help!

Feel free to check out summer camp overviewif you want to see what I am up to!
27 Mar, 2021 21:30

This is an interesting species, and I particularly like the part about the mead.   I do have one suggestion though. It is a bit unclear how the harpoon is activated throughout much of the article, as it is not explicitly noted that the channels are pressure sensitive until near the end. I feel like at the beginning of the article, perhaps under the quote, could be a short summary to tell us that the plant shoots the harpoon up at its unaware victims who wander too close (who stepped on the leaf mat?).   Which leads me to questions. How far from the main cactus do these harpoon channels extend? Are they activated if any part of the leaf mat is touched or just if the creature is standing just above the channel? Is there anything about the plant (other than the lyrebird, which is a nice touch btw) that lures victims closer? Is it the promise of water in the leaves, or perhaps the fruit - is it brightly colored, sweet smelling? How many harpoons does the average cactus have, and is it fairly useless while the harpoon is activated? Does it stay embedded in its victim? retract? break off and regrow?

- Hello from Valayo! And Happy Summer Camp!
12 Apr, 2021 02:07

Thank you so much for the feedback and questions. I have been sadly busy with the "fun" of changing jobs and moving, but have taken down notes so that I can hopefully add to the article once I get more settled and have time again as I really enjoyed coming up with this concept.

5 Apr, 2021 12:24

You had me at 'Harpoon Cactus', and making it a blood-drinking menace made it even better. But what really makes the article shine is the way you've woven it into the fabric of the world; all the context details like the lyrebird, the disappearance of the Charred Brigade, the brewmasters offer... Those are things that really make the article come to life and make it part of the world as a greater whole. Really great stuff! :D

13 Apr, 2021 19:49

Holy friggin' crap. I started out reading this like "how bad can a cactus really be" and ended with "jesus shit stay away from the damned thing". I especially liked the quote by Hugo since that really, really drove home just how awful these things really are / can be. I can't even imagine how awful it would've been for the man. o.o   For science! I can appreciate that he was told to record things even as the guys were dying though. There was just so much good packed into that brief quote. It was likely the most impactful thing. I also love that bit tacked on at the end of the Interspecies Relations and Assumptions where an entire brigade was just lost to not only these birds, but presumably the cactus it led the people to.   Such an awesome plant - a terrifyingly awesome plant.

What would an ocean be without a monster lurking in the dark?
13 Apr, 2021 21:28

Murder blood-plant! And what do scientists do, they want to sample it... "Your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should."

Too low they build who build beneath the stars - Edward Young
16 Apr, 2021 01:23

Hey drunkenpanda!   I like the interspersion of 'science' throughout your article to give the harpoon cactus some realism. My biggest criticism is I didn't really notice where you discussed the mechanics of the harpoon used to attack prey. However, I do like the description of its hemovoric behaviour supported with the "Last Retreat" and "Hugo" excerpts. Well done!

xtremepsy | Ölütanrı
Checkout my other favourite entries to the 2021 Peculiar Plant HERE!
Feel free to read, favourite, and comment on my entry, Digivine.
17 Apr, 2021 01:43

Hey xtremepsy,   Yea, I have the mechanics sort of worked out, but have been in the process of changing jobs and moving, so haven't really had the time to update the article sadly. I had a lot of fun figuring out how it would work and am looking forward to getting it onto the page, but that probably wont happen until early-to-mid May when my life will hopefully have settled down a bit. but for a quick visual I took a lot of inspiration from harpoon cone snails.

17 Apr, 2021 14:57

No worries! All things in time :)

xtremepsy | Ölütanrı
Checkout my other favourite entries to the 2021 Peculiar Plant HERE!
Feel free to read, favourite, and comment on my entry, Digivine.