Something strange happened in my fort and I have no idea what exactly it was.
My dwarfs were just moving along as usual when it looked like I got an alert saying that a schizo dwarf started acting up and was disturbing the other dwarves. He didn't seem to be hostile so I didn't do anything about it and just thought it was kind of funny. Soon after that my militia commander suddenly put down the schizo and I thought that was the end of that. Strange but I had some idea of why it happened.
Then the strange thing happened. My commander went on attacking other dwarves just if they are close enough. I didn't see anything saying that he went mad or was throwing a tantrum, in fact his current job listed was going to a training exercise or something of that sort. He began to chase a bunch of dwarves into a mineshaft with two exits and after the dwarves he was chasing got away (he got distracted from beating someone to death) he just stopped moving, seemingly only reacting by giving chase when a dwarf gets close, and stopping again when no prey is nearby. I thought I could wall him off but dwarves are stupid. Even though I marked the entrances of the mineshaft as being a restricted traffic area a bunch of dwarves still kept trying to get in before the wall was complete.
So yeah, he got out, starting attacking and killing whatever was close until he got a boot to the head by the fortress' doctor and died.
However before that happened I did some experimentation. I tried sending the militia to kill him but I couldn't target him. I tried removing him from the militia (by disbanding the militia, and replacing his status as militia commander) and saw that instead of attacking dwarves that were close he ran away from them. I tried targeting him again for the militia to kill but they still couldn't target him. I put him back into the militia and he went back to attacking dwarves for the crime of being too close. Eventually his rampage ended when the fortress' doctor gave him the good ol' boot to the head, killing him.
But that wasn't the end of it. Not long after that, a ranger (again with no clear health issues, no tantruming, no alerts explaining what happened) just began to attack dwarves left and right. At the very least, the militia commander had a legendary weapon my archaeologist dug up that kept going on about "bound demon souls" or something in the combat log which I thought could explain what was going on, but the ranger didn't have that weapon or anything innocuous looking.
Since it seemed like my dwarves were just randomly turning violent and because it was late, I dug down to the circus to get some clowns to liven up the place. Then the clowns got stuck on a floor hatch and didn't seem all too interested in coming up to play so I tried to abandon the fortress to leave behind the whole "dwarves turning mad without turning mad" thing that was going on. Then the game crashed on as it was closing down.
Yeah... I would really like to know what happened. I would've accepted that a schizo dwarf going around attacking and killing other dwarves for seemingly no reason, but both the commander and the ranger didn't seem to have health issues. I would've accepted tantrums or a dwarf just going mad and doing all of this but neither seemed to happen. I would've accepted a demon possessed weapon making my dwarf go all hostile but the ranger wasn't carrying it when he went psycho. That I couldn't target my commander with the militia really bugged me too since when dwarves went mad or threw hostile tantrums on me before I remember being able to put a hit on them; though I do not remember if I could or could not target the ranger since it was late and I was losing interest. I could not find any clear explanation so I hope someone out here would know. It really killed my mood when my dwarves were just going psycho for no apparent reason with little I could do about it.