It's gotta be the 164 Dwarfs, of which 50 are children, 50-60 PETS (not just animals, pets) and then the Elven caravan coming at EXACTLY the same moment as a goblin siege AND my entire fort was out in the fields collecting narrow crap from the LAST siege I had...
164 Dwarfs + 20-odd Elves + some 200 goblins = Massive slaughter for both units AND FPS.
I swear it was at 1 FPS for 2 hours until things finally started moving again.
When it was all over.. My 50 children were all alive and well in my meeting area, and ONE marksdwarf who happened to be up in my fortified tower at the time and just picked off the goblins afterwards.
There's nothing like seeing 350 bodies and the armor/weapons/clothing for all of them in a 10x10 area. Remember all the pets? They followed their owners into battle. Guess what happened. Go on, guess.
Final Count:
1 Dwarf
0 Elves
0 Goblins
1 Cat, owner being the surviving marksdwarf. Bet you weren't expecting that!
50 Dwarf Children/Babies
And with the lack of anybody to keep food supplies up, everybody starved and Glacierlashed was no more.
I'll admit, losing was fun.