The end of my last fortress was such a hilarious face palming all the way through that I still have a sore forehead.
I mess up my levers first in a goblin siege, which results in getting a full unit of ten crossbowdwarfs slaughtered right next to fortress gates. Better equipped melee dwarves return the favor to all but last remaining two goblins, and I take a look at their general condition and think they will die very soon. So I remove burrow restrictions.
All my civilians start pouring in to the melee of 2 goblins & 10 dwarf soldiers, in an effort to bury the crossbow squad.
Somehow the half-dead goblins manage to slaughter ten civilians right to the fortress gates, too.
Those were all my mistakes, though. Can't blame the dwarves (this time) around.
Yet only half a month passed, and a were-porcupine arrived. It literally bit a soldier dwarf in the toe, and another civilian to the tummy before it went down.
I didn't want to take any risks, so I ordered the two that were bitten to have a nice little get-together at admiring my waste disposal system from the inside, and maybe have a little lever-related accident.
Civilian went there haplessly without any ill doubts, but the soldier dwarf never showed up until it was full moon again, and the slaughter began.
Every month thereafter saw an outbreak of were-porcupines, and I thought that there would be no chance of me finding out all the infected members, so I just didn't care anymore.
I had a small drophole for captured goblin invaders, where I could drop them from a height that injured them badly, but not lethally, to a cavern. In time I had wanted to make a goblin colony there. Perhaps even throw two picks and two axes and some other provisions down too, to see if they would make it any better than my own fort.
Anyway, earlier I had been dropping them one-by-one to avoid any prison revolts, but this time I ordered a mass-dump of eight goblins.
Dwarves managed to throw first one down, but second in line escaped, and all the six dwarves behind got horrified of a naked, escaped goblin - and dropped their own leashes. So all the while a porcupine-epidemic was raging in the fortress, seven naked goblins were running around and causing chaos in the tunnels below.
Finally all the goblins were killed and the dust had settled from the epidemic (all the infected dwarves were too badly injured so they couldn't land any additional hits even while transformed) and my once-glorious dwarven population of 120 had been reduced down to 19 surviving members.
Hell yeah!
I'd continue this. From the ashes would rise new and improved dwarven empire.
Well.
There was not enough burial space, so ghosts started popping up like mushrooms.
And then outpost liaison comes around.
But it's not outpost liaison from mountainhomes...
As an ultimate testament to the failure of absolutely everything, mountainhomes had been conquered by goblins.
That must have been the most !FUN! I've ever had.