It's spring again, which means I have like 80 elves wandering around trying to kill my herbalists. Once they were seen I sent the civilians inside, and the 56 soldiers we've got (26 marksdwarves, 10 hammerdwarves, 10 macedwarves, 10 speardwarves) were sent to meet them at the gates. Since we've gotten enough metal armour for the hammer, mace, and spear dwarves the elf weapons have become a non-threat. Even arrows bounce harmlessly off bronze breastplaes and steel helms. Our only injury was a hammerlord who was wrestled to the ground and beaten by 5 of them until another of her squad bashed their way through the horde to help.
Unfortunately, there's now a lot of bodies to try to clean up. This... might take a while.
Edit/update: Cleanup looks like it will take most of the spring. We have the bodies gone at least, so no more horrified dwarves sobbing about dead elves, but they left a lot of pretty much worthless wooden armour and weapons that need to be cleaned up still.
The one injured dwarf ended up dieing in the hospital, before even being diagnosed, so we lost one hammerdwarf in the exchange. Shouldn't be too hard to train up a new one to take up her Masterwork silver hammer, but, it's always sad to see a dwarf die to elves.
Edit/update 2: Cleanup took until nearly the start of summer, as anticipated. In the meantime, the engravers finished engraving the arena, and all of the bedrooms, dining halls, meeting areas, temples, etc. We built some archer's nests in front of the gate into the fortress, to keep them away from the melee when the elves inevitably return, and our best armoursmith was tasked with taking what was left of that strange blue metal into a suit of armour for the militia commander, the only pieces not masterworks were a boot and the gauntlets. I doubt there is a better protected dwarf anywhere else in the world right now.
Unfortunately, with our civilization on the verge of collapse, we're not able to advance to a barony, or county -- no sites have been founded nearby, despite our obscene wealth, and the hundreds of elven invaders our legendary militia has bludgeoned the teeth out of, and so, Atistathtat "Stakeplunged" has been retired, at least for the time being. Perhaps this shining beacon of dwarven opulence will be enough to hold back the elven onslaught and breathe new life into Egstakalath "The Evicerated Bolts", our parent civilization. Time will tell, I suppose.