I only just started playing Dwarf Fortress the other day, and I'm already hopelessly addicted.
I started off just playing adventure mode, as the main game seemed too daunting to me...
But just yesterday I started my first proper fortress. Of course, at first I had no idea what I was doing, and it was a long process getting my dwarves to do anything at all.
Well, by the time I'd dug out some caves and figured out (partly) how to build things, a lot of my dwarves, and new migrants, were pretty frustrated. Eventually a couple of them lost it, and killed some of my other dwarves...
My first reaction was to command my soldiers to kill them, but I couldn't. (I have no idea how to mark them an enemy or anything like that
)
So then I discovered the JUSTICE screen. I looked through all my dwarves for a candidate for a sheriff, eventually I decided on a recruit in one of my squads, a new migrant. He had no friends, so I figured he would make a good dealer-of-justice, having no ties to anyone. I made him Sheriff, gave him the title of executioner and a massive axe, as well as a trendy black outfit!
...Bad move.
I think he was a bit unhinged to begin with, but giving him an important job made him go completely nuts...
He was pretty handy with that axe, and killed about... 30%? Of my dwarves.
Of course that didn't include the two criminals. *sigh*
After that, he was okay for a while, dishing out justice, and only occasionally going nuts and lopping off some heads. Eventually, though, I think I only had about seven dwarfs left, and he was posessed. I have no idea what by, but he just sat there in a 'strange mood', not moving.
He sat there for ages, until eventually he went 'completely insane', became a clothier, and got brutally beaten to death by another dwarf.
I guess I did something wrong in choosing that guy... But damn, that was fun.
I'm really addicted after that!