Tanglednets:
Backstory:
Tanglednets is a 9z-tall tower surrounded by a 2z-tall outer wall with a bridge raised 1z up connecting the tower to the outside world. It was originally built directly on a river, but recent progression with the tower required the river be diverted.
So I dug out a 4z-deep trench in a circle around my outer wall, leaving the river in place until it froze during winter. Then carefully channeled the ice and dirt out, leaving a frozen river looking out over my trench.
That's when a necromancer showed up at the head of 44 undead. By the time I had built 45+ cage traps to catch them all, Spring had come, and the trench was filling quite quickly. However, I should have located my cage hall entrance better. Fully half the undead were in the north-east of the map when I opened up the west-facing trap hall to them, and they took the shortest path... right into the lowered-water-level area of the river emptying into my trench.
Roughly 20 of them, plus the necromancer, were washed into the trench, and refused to path out. The necromancer died on impact, but the rest just sit there. Keeping me under siege and shooting at passing Buzzards all day (though they did attract, and murder, a were-iguana, so I do owe them for that)
With no recourse (no military at the moment, and many of them were ranged) I decided to wait them out
Very satisfying
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