My most recent fort was a fort of firsts.
First mayor, captain of the guard, more than 40 dorfs for more than two seasons, siege, ambush, and opening the HFS prematurely.
Normally, my forts die of some internal issue, fps, boredom, or my own shortcomings before they can be attacked.
First, we have the ambushes and sieges. Summary: two seasons, two ambushes, two sieges; All enemies slaughtered, Goblins: maybe a cripple, Custom Orcs: 3 perma-cripples and 6 dead.
Goblin spearman have an exceptional ability to hit the right foot.
Then, as I was preparing my horribly bloated fortress for adventure mode Fun, and also getting ready to move on to a new fortress with my new ideas, by mining blue rocks for my adventurer, I discover that my blue rock section had a hole in it, straight into the HFS. Snow, ash, and flame clowns overran the fortress after a while as the five soldiers that actually responded to my orders were only able to kill about ten of them before suffocating and being smashed against the walls. As the clowns were running about slaughtering dorfs (including the mayor, who liked bogeymen "for their terrifying antics"), Criminal Minds was on in the background and had just quoted "God sends meat, the Devil sends cooks" at some point in time five minutes plus or minus the breaking of the final defenses. It occured to me that I had heard this quote before (Dynamix's Starsiege, Sax says it periodically), so I pulled up the sound file, listened to it a couple of times and corrected it to "Armok sends meat, the Devil sends cooks."
Later, adventurer goes in, discovers that adventurers can pick locks, and promptly slaughters around 25 clowns before DF crashed.