I'm not sure what exactly caused this, so I'll give some background info in case that helps. I was in the CoC (my first time ever making it that far), and somewhere below Dwarftown (if I remember correctly it was the level where when you descend down into the level you see the other staircase as well - though it could have been below that one). Anyway, I found a beehive, and - with my music skill worked up to 100 - I had fun kicking the beehive and then playing my mandolin (which I believe is spelled wrong in ADOM as a side note), and watching bees sting each other and collapse. Occasionally I would kill bees myself as well.

Finally, the queen bee came out. I led her into another room and played music. She became tame. When I brought her back into the room with the (now empty) hive, I got a message something along the lines of "The queen bee gives the queen bee a weird look." There was no other queen bee for her to be looking at. This is when things started getting pretty weird.

At this point (possibly a turn or two after the message), I pressed a key on the numpad to move, and the game suddenly saved and quit. (No "axes high!" message for my Dwarf either.) I opened ADOM, loaded the game, and tried to move, with the same thing happening. I kept restarting ADOM with the same result (I didn't try any other saved games, it should be noted.) I found I could access things like my inventory or skill list without the game closing, but things like moving and other actions that take a turn would make the game save and quit.

It gets worse. After maybe the tenth time this had happened, I tried to move my character, and the whole game froze. The game within the ADOM window started shaking and flickering. Nothing could get out of it. I had to force-quit the program and - of course - lost my save file. After force-quitting, when I tried to open ADOM, the home screen flashed for a second and then disappeared. The game, it seems, instantly quit. Now every time I open ADOM, the home screen flashes and then instantly disappears.

Weird.