Chaos, disorder and Dwarf Fortress.
What do you mean by "and"?
If the slush demons are not moving and in the magma pool, a single bucket of water dropped through a grate from above the tile they are in will form obsidian and kill everything under it all the way to the SMR.
All I would've had to do if they just stayed in place was mining out a single tile and pulling a single lever. Unfortunately...
...the banshees decided to move to the forges, and then up until they finally stopped 2 z-levels below the blockaded first caverns exit, slamming some cheetah cubs and kittens into walls on the way there. I surrounded the exit with fortifications, taking care not to leave a way of escape through the ceiling, put an artifact pig bone door in there, and ordered the floor blocking the stairs deconstructed. One jumped out rather quickly, and marksdwarves shot it to pieces. The second one was more reluctant. I unlocked the door, hoping it would get the demon to move - and a civilian walked inside. He was lucky enough to get kicked through the fortifications before suffering too much damage, however his lower spine has been destroyed and he'll never walk again. Still, the plan has served its purpose well.
Then the soldiers went down to kill an ash demon hovering in the lowest caverns, and suffered some unnecessary casualties due to being stupid and walking straight past it to the assembly point. The Lauded Lances, a squad which used to be stationed on the surface alongside The Primitive Daggers, guarding the western side of the fortress for years, was reduced to its last member and subsequently disbanded.
Anyway, only 5 demons are left, 4 made of fire and one of salt. The salt one is stuck in the shaft I used to drop old furniture into magma, one fireclown is walled off in a corridor just above the third caverns, another one is hanging by the magma pool with no intention of moving, and the last two sit in an unused shaft with a ballista pointed at them. The old magma forges are considered reclaimed, and are currently being cleaned up and restored. All dwarves are so busy that no one had time to go and trade with the dwarven caravan. Everyone is hauling everything everywhere.
The project which was meant to kill the banshees hasn't been abandoned and will - after some slight alterations - serve as an obsidian factory. If everything works as designed, that is.
Three things I forgot to mention before:
- Something actually did show up on the surface - more precisely, a minotaur child. Since the soldiers were busy underground fighting the demons, I sent some crossbow-bearing civilians on the walls. A flurry of bone bolts made short work of the monster.
- Back when I was setting the anti-demon upright spears in place, my chief medical dwarf was attacked by a tick devil. The ultimate cause of his death? Being scared by a murderous ghost. While being torn apart by a gargantuan monster from hell.
- My new hammerer has a ghostly dwarf on his kill list. Dwarven justice reaches
everyone.
I did some research and found the DFhack command for clearing the dead units list. Over 2500 entries were deleted. I hope that fixes the immigration.
And the saddest thing for the end: the expedition leader and founder of the fortress, dedicated manager and bookkeeper for about 24 years, Bembul Cosmosgorge, is dead. She has apparently stepped into some forgotten beast goo scattered near the well and bled out on the way to the hospital. She will receive a platinum sarcophagus and an engraved tomb in return for her loyal service.