I have finally eliminated all 120+ goblins that where occupying the 2x2 map, and I managed to manufacture enough iron and flux to make full steel armor for all 30 of my dorken residence to use.
The bountiful loot ( mostly goblin sized clothing ) has made wonderful trade goods, ensuring I've been able to get everything my fortress has needed.
While digging exploratory tunnels, probing for magma pockets + adamantine column locations, I unexpectedly ran into a very deep adamantine tube going down into the underworld - triggering the demon invasion event. I was not prepared for that at all.
Several miners died as I equipped my first squad, lead by the expedition leader, with the best weapons available including the couple adamantine battle axes that where already produced.
They bravely marched into the narrow lower hallways and held back the demon swarm just long enough for copper walls to be constructed behind them ( fastest material I had to build walls with ).
At that time I had reached the population limit of 30 dorks, 2 of them children. I also had 3 goblin monster hunters.
All 3 goblins died, along with 19 dorks.
After building a gabbro wall behind the copper, flood tunnels where dug from magma pools to the lower hallways and hooked up to a master lever. 2 more dorks died in that construction effort, but no demons escaped into my fortress complex.
The order was given - magma flooded the lower tunnels from several directions, gradually pushing the demons out and back down into the underdark. After over an in-game year, water was brought down from the lower caverns to the top of the adamantine tube and held in a large protected cistern.
The magma flow was shut off, allowing it to drain to the point it was pretty low down in the adamantine tube, at which time the water reservoir at the top was rapidly dumped down, creating an obsidian plug near the bottom.
The mess I created is a pain to deal with, but at least my fortress is still alive and the surviving dorks have not all revolted yet. On a side note, a demon was killed ( somehow ) and ended up getting butchered + cooked ... the dorks have been eating very well from all the demonic meat.
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