Fun is defined, in the Dwarf Fortress community, as being anything(whether demons that come hurling fireballs from that one adamantine vein you were stupid enough to mine out completely, floods from the aquifers you idiotically dug into, dehydration because you forgot to build a well for the winter, insane dwarves stripping themselves in public and going on killing sprees, dwarves turning into wereelephants that murder your entire military, or just plain murderous wild elephants that are the bane of Boatmurdered) that might cause you to lose the game.