Hi. I’m Squamous, one of the organizers of the Dwarf Fortress mod jam. To give an example of what we’re looking for in the mod pack, I’ve created a sample submission which I hope will serve as an inspiration for anyone looking to submit something, along with a few neat tricks I think more people should know about and the general process I went through to design it.

So, I present for analysis: the flying fumer!



A creature of the caverns, the flying fumer is intended to slip seamlessly into that ecosystem and act as another bizarre inhabitant to contend with. The name was chosen after looking at some of the more DF-unique cavern dwellers and noting the vibes they tended to go for. To me, the energy here is oldschool DnD; draltha, gorlak, green devourer, voracious cave crawler, aboleth, beholder, githyanki, rust monster. Fictional gonzo nomenclature or descriptive titles. I went with the latter here, as its ability is the most distinctive thing about it.

The fumer’s primary weapon is its ability to spew acid, a particularly nasty kind that will melt flesh right off your bones. If it hits you, you have seconds to wash it off to stop the damage, and even that’s no guarantee of survival.

The mechanism behind it is the same as the fire imp’s fireball or the force push of an elite undead, an interaction. However, for vanilla creatures these attacks are instantaneous; if they see you, they instantly use their attack. Here, the fumer will inflate its throat sac, readying itself to disgorge its lethal payload, and you have a brief window of time to react. The option presents itself to duck behind a corner and try another path, or, if you are brave, charge forward and sever the sac organ it relies on to use its special ability. It adds an additional layer of tactical flexibility and player skill, rewarding careful and intelligent gameplay, and presents multiple approaches to the problem, including just fleeing before it attacks!



In addition, a few other tweaks make it stand out from conventional monsters. It lacks the [LARGE_PREDATOR] tag; it won’t appear in worldgen as a creature to slay, and won’t instantly attack people either. Rather, it uses PRONE_TO_RAGE as its mechanism of hostility, acting more like a belligerent prey animal such as a hippopotamus or goose than a wolf or lion.

There are also some notable weaknesses which grant greater control to the player regarding how they engage with the creature. For one, it is very slow, even in the air, allowing it to be outran. Secondly, it emits a loud sizzling noise as its acid drips from its mouth, which can be heard from across the map. This informs the player of its presence and allows them to proceed with awareness of the creature in mind. Even if they don’t encounter it, the knowledge it is out there lurking in the dark adds tension to the exploration.

It also has a nasty trick it can spring on unsuspecting attackers. While it typically disgorges a blob of acid from afar, if a foe closes to melee it can unleash a jet of corrosive fumes, the true origin of its namesake, that can completely cover a victim in its flesh melting acid. Mercifully, it seems that there’s only a 50% chance of it having this ability for each inflation of its throat sac. Do you want to take the chance?

Bear in mind, this kind of nuanced control and engagement is currently only possible for adventure mode. Fortress squadrons charge into battle without consideration for delayed attacks or lethal breath weapons, so they’re a bit trickier to maneuver. Even so, by moving the squad to flank the creature, ensuring that when they enter its line of sight they are closer to it than they might otherwise be, the player can still increase the odds that the beast is killed before it can use its signature move. And just by passively existing, it presents an obstacle and puzzle to players of either mode; if it's blocking somewhere you need to pass, how do you get by it? It exists as a hazard/puzzle/area denial type monster, something difficult to approach, but easy to escape.

Some other fun facts:

-They can sometimes appear as a pair in addition to one creature, for double the trouble.

-If you manage to puncture or sever the fume sac, acid will spill out of it, and can potentially get on you or just pool on the ground.

-On that note, clothing may protect you from the acid globs, but not the fume spew attack, as you can breathe it in and melt from the inside. Shields can still help, however.

-The acid evaporates if you leave it alone, meaning they can’t paint the map in flesh melting fluids (that might be a little too cruel to inflict).

-I’ve severely nerfed its strength value; it isn’t meant to be able to kick you to death (unless it gets lucky). Without this, it is a mound of muscle over three times bigger than you rather than a wormy turret, and Dwarf Fortress would treat it as such.

-They can be tamed, domesticated, and ridden. Goblins may well appear mounted on them! However, the fume attack will likely still soak the riders, meaning that inciting that ability could prove mutually fatal. For goblins I imagine they’d still try it, but bear that in mind if the opportunity presents itself to mount one yourself. For this reason I’ve given them the [EVIL] tag, keeping them out of the hands of peoples with stronger self-preservation instincts.

-If you neatly sever the throat sac, it is worth 50x as much as parts from the rest of the creature. Puncturing or otherwise crushing it won’t do, so have fun with solving this challenge!

All of this was done without any use of graphical sprites or lua scripting; as long as you study the modding tools, you can make something just as complex, nuanced, and (hopefully) fun to encounter as this creature without needing to be an artist and a coder, so don’t feel intimidated! We do of course welcome artistic depictions and fancy functions as well, but the point of this sample is to showcase everything that can be done even without them. All you need is the wiki and your imagination.

Additionally, the sample also serves as an example of formatting; you can see how I put SQUAMOUS_ at the front of my creature, interaction, and body files. This is to prevent duplicate raws and other conflicts with the vanilla game and other mods. It’s important!

In order to ensure maximum compatibility, I’ve uploaded the file on DFFD, the Dwarf Fortress File Depository. It’s a trustworthy means of storage for Dwarf Fortress content, and doesn’t require an account to download things from.


As for general advice, here’s a few things that help me work, but do what feels best for you:

-When making a creature, an easy shortcut is to find the vanilla creature that is closest to what you’re already looking for and using it as a base to remake into your own thing. You don’t need to create it from scratch! For example, if I wanted to create a giant, predatory weasel, I could modify the wolf or giant rat creature and with just a few tweaks I’d be getting there. Then I could look at how the giant cave spider shoots webs, and add that feature to it, and now we’re cooking with gas.

-Test your creature both in arena and in-game. Arena mode is great for testing certain things, but the way it can force hostility and compel fighting creates conditions that never appear in actual play. A mechanic that works fine in arena mode might not behave in the game proper!
Consider how your creature works in both adventure and fortress mode. This might be a bit of a no-brainer but when precision of control and even just timescales are way different between them, keeping in mind how they behave in both prevents any issues in either.

-The wiki is your friend! All tokens (the discrete bits that make up something in the game) are documented exhaustively. If you see something in the file of a creature, it is almost certainly explained in detail somewhere.

-This is more my personal advice than objective ones, but for the purpose of making a monster to add to the bestiary, consider not just style and aesthetic creativity, but the niche it serves and the challenge it presents. The flying fumer is an area denial monster. It exists as an obstacle and puzzle to be navigated on the way to somewhere else. It has particular strengths and weaknesses that incentivize tactical play and learning its behavior. Think about what might present interesting, unique challenges to the player.


But above all, have fun with it! The purpose of this jam is to showcase the power of Dwarf Fortress’s modding tools and let the fandom’s creative energies flow, so don’t feel like you’ve got to put out something artistically perfect or immaculately designed to be eligible. We’ll also be happy to help sand off the rough edges if there’s an issue here or there, and will be giving feedback on the submissions we receive.

Happy modding!