Hmmm, been thinking to do a topic like this meself.
There were few happenings that led me to this idea, all in the same fort (which I have not touched for quite some days now due to some other thinkgs)
So.
This fort possesses a drawbridge at the entrance. Underneath there is a migrants starvation chamber with a single doored entrance. Among others a horse and a cow came with some migrants and become "traped" with the fresh recruits stationed there. After migrants died, animals remained in the chamber. So one day a kobold thief opens a door to this chamber...

Yes, DWARFS' domestic animals of the ARE to be feared
Another proof:

This fella had to be taken down by a military, aye.
And for the FUN stuff:
I finaly stumble upon the PIT.
"Fine" I say, "Lets wall it off and let those buggers sta--"
*paused* "Horrors! Demons of the deep!" *unpaused*
"Oh now that was qui--"
*paused* "Horrors! Demons of the deep!"
"Uhhh, a wall, yes, wall.." *unpaused*
*paused* "Horrors! Demons of the deep!"
"Damn! You, legendary miner over there! Become a recruit! *unpaused*
*paused* "Horrors! Demons of the deep!"
"Wait, didn't I have some odd 20 champions stationed at the front gates? Station at the pit! *unpaused*
*paused* "Horrors! Demons of the deep!"
"Oh shi-- my legendary mason is trying to construct that wall! You, get out of there!" *unpaused*
*paused* "Horrors! Demons of the deep!"
"Shave me bald and call me an Elf, WHY are YOU trying to put that stone on the stockpile when there are OHGODSTENTACLEDEMONS on the path between you and that stone??!!" *unpaused*
*paused* "Horrors! Demons of the deep!"
"Oooohhh snap, where by the Armok is that military?!!" *unpaused*
*paused* "Horrors! Demons of the deep!" *unpaused*
*paused* "Horrors! Demons of the deep!" *unpaused*
*paused* "Horrors! Demons of the deep!" *unpaused* ...
I lost few good dwarfes like one legendary mason, legendary miner, legendary carpenter...Apart from the constant "Horrors!..." message and it companions I was greeted by a horde of insane peasants, elves and human civilians fleeing from the accursed chambers, severely droping my fps...
But appart from eminent tantrum spiral which costed me some additional most of them useless woodcrafts and soapmakers, I pulled out. At the end of the massacre, I counted 33 demon corpses
They...they just keept coming... O.o
But now I am wiser for one additional fact:
Tantrum spirals are EXCELENT to train your masons in making coffins and your engravers to smoth/engrave tombs.
I must have more tantrum spirals.
Oooh yesss, mooooorreeee...