Yep, the picture in the spoiler is my current fortress' cavern layer/farm. You're probably wondering how I got into this situation.
So I was inspired by one of the stories in this forum to build a fort in a terrifying glacier. My initial plan was to dig down to the caverns and use that as my farming area. I'd genned the world to make it a single cavern layer to speed up the FPS rate, and when I found the caverns I saw there was a big patch of land that could be used. Pretty simple, right?
Except I'd put a Deep Ones mod in my raws that adds an extremely powerful, yet non-aggressive, madness-inducing Elder God into the deepest caverns. When one Elder God showed up, I decided to wall off a farm/well area for my fortress. Everything went according to plan... except for the undead crundle (and a few non-undead ones) that traipsed into the half-finished walled area, forcing me to send my militia to kill it. By the time the crundle situation had been settled, the Elder God had popped up right in the middle of my walled area. I sent in my militia of
two dwarves.
Big mistake.
The Elder God smashed the hammerdwarf's head in, then chopped off the axedwarf's leg clean below the knee. (The axedwarf would later go stark raving mad from lack of sleep and die.) Then, it sauntered up the door, having gained the name "Anguishedplans", and headed for the entrance. The rest of my dwarves just watched Anguished go past them in the corridor ("Oh, 'sup Cthulhu. How's it hanging?") as it went out the entrance, up the glacier, and off the map.
I was shocked. In my hubris, I had unleashed an unholy thing from the darkness before time onto the world, probably dooming it. For a moment, I pondered save scumming.
Instead, I decided to play the thing through, which involved finishing the farm walls, clearing out the sudden influx of scuttling, octopoid body parts, and trying to ignore the fact that my dwarves were all gradually gaining the Innsmouth look. It went well... until the food ran out. In desperation I had my dwarves attempt to kill a troll that had wandered into my common area, in the hopes that it would give us meat. Instead, they punched and kicked at it until they got exhausted, passed out, and then went back to it, not giving a shit that they were starving.
And then the fort's cat ran out, got caught in one of the clouds of foul fog that occasionally roiled across the barren icy surface, and turned into a thrall. While I had created a pair of doors on the entrance of my fort and locked them (the "airlock" setup), keeping the thrall cat out wouldn't stop the dwarves inside from starving. Deciding that this was pretty Fun, I let the cat in. As expected, the cat began to maul my dwarves, killing several through massive blood loss.
Just as I had given up on the fort, however, a migrant wave appeared, and one of those dwarves killed the cat thrall with a blow to the head. It was, however, too late for all but one member of the original 13 that had resided in the fort, who had been killed by one of the dwarf corpses that rose up in the aftermath of the massacre.
But at least Ghoulbreaches lived another day.
I decided to make the most of this second chance, and built a fairly good fortress. Sure, there was a second Elder God in the deep, but my walls were complete, so it couldn't come inside, right?
Then it proved me wrong by showing up inside the walls.
I trapped it in the airlock to the farms and dug another one, then examined the area where I'd first seen it.
Turns out the fort's well was built over a slope. That must have been where it came.
I facepalmed, then built a floor over it and moved the well to somewhere without a climbable area. Then a Forgotten Beast with the fever-causing dust showed up and chased some crundles around. I didn't give a damn because it was outside my walls-- but when I spotted a crundle with a name on my units list, I checked it out.
Turns out this crundle had killed the Forgotten Beast by making it bleed out. Good on the crundle, bad for my fort, because now I have an undead, dust-spewing nightmare right outside my walls.
On the plus side, I have a last-ditch weapon to use in case a Forgotten Beast or something worse makes it into the fortress. Sure, it'd doom my dwarves to succumb to its dark will, but if it comes to that then the fort is pretty much doomed anyway.
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Bonus screenshots for the rest of the fortress:
1- Fortress entrance, with a double door setup so in case something bad gets in I can lock it and trap it in the corridor. This setup is everywhere in the fortress. The door at the other end is an artifact door.
2- Training grounds for the militia. Putting it here means that they can quickly respond to anything that gets through the airlock and/or reanimates in the butcher shop.
3- Communal living space for the dwarves.
4- Food & booze storage-- I picture it as a sort of walk-in fridge.
5- Kitchens, fishery, and 2 stills, for production of meals, prepared fish, and drinks.
6- Route to depot for caravans. Double bridges allow me to seal things in the passage should something unpleasant enter.
7- Temporary stockpiles: will be moved to the warehouse built above the workshops eventually.
8- Butcher shop and drop-off pit for corpses/reanimateable parts. The pit drops into an atom smasher setup.
9- Stairs. Leftmost ones go to the workshops, rightmost to the forge and farms.
Bedrooms. Upper part is for regular residents: lower part is administrative quarters for manager, bookkeeper, and U.R.I.S.T.* facility administrator ("mayor").
[* U.R.I.S.T.-- Unsafe Region Incursion and Settlement Tactics]
Forges. To the upper left is the garbage compactor.
Workshops.