I usually run relatively safe forts (yeah, yeah) so I don't often have a reason to post here, but today I have had a... 'worthy' encounter with fun.
One of my four uninvited guests somehow managed to breach my primary mining shaft from the third cavern level and work his way up the inhabited part of my fort, where he proceeded to thrash a skill-less peasant. This had happened once before and I was pretty sure I had gotten all possible entry points (entry only seems possible if creatures can move diagonally through z-levels, and then only if they can fly. Which this one could... but then all the ones I've gotten could). Whatever the case, I wasn't very worried - It and all the other ones I've gotten so far were organic. I immediately recruited my entire fort and sent them after the beast.
what ensued was a massive dogpile in the only three squares adjacent to the beast (including the one it was standing on), followed shortly by its death. His death was followed shortly by the death of the peasant he was attacking, but this didn't worry me either as he was a newly arrived immigrant who hadn't had time to make friends. My only real concern was that his 'deadly blood' would melt my fort at some later date, but there wasn't really anything I could do about it - his blood was already covering a high-traffic zone. I could only hope it wasn't that particular toxin.
But it turned out doom was much closer at hand. Shortly after the death of the peasant, the one other wounded - a pet puppy - died. Once again, this didn't bother me; his owner was also a skill-less newly arrived dwarf with average strength. He immediately tantrumed - I ignored. That is, until me punched one of my two almighty champions in his iron-clad head, instantly killing him. What?
...I then savescummed. Yeah, it was kinda funny. Yes, I had a legendary dining room and good food and drink, and so it wasn't likely to mean the end of my 37-dwarf fort. I could have played it out. But I just don't like losing my dwarves. Especially the legendary champion of my original seven. Especially to a skill-less, strengthless newly arrived dwarf. In one punch. To an iron-clad head. Because he tantrumed. Because his puppy died. Immediately after said dwarf and many others slaughtered a forgotten beast.
It was funny. But it wasn't going to stick... though I suppose in hindsight I could've just sealed that peasant in a wall somewhere to reflect on what he had done until he dies of starvation.