So I have a rather strange situation at my current fortress and was looking for advice on how best to deal with it: Outside my walls a battle has been raging for nearly a year between a humanoid lizard demon/deity and a busted up goblin skeleton. While they're far enough away that the constant lethal dust explosions aren't an immediate threat, it has still caused me some problems.
Some background: The Demon arrived with human merchants as their diplomat. At the same time, I received a house call from some necromancers. As it was my first encounter with the undead, it took me some time/wiki reading before I got a handle on the whole situation. Eventually two of the necros walked into my saw-bladed entrance and the third was outed and ran for it. Unfortunately, a handful of there minions were now in combat with the Demon, who had bumped into them on his way to the fortress. The demon has a boiling dust attack, and that's about it apparently. Said attack, while liable to melt any of my dwarves in the area (I had a front row seat for the following dwarven caravan's guards attempt to break up the scuffle - not pretty)doesn't seem to harm the skeleton. Originally there were three or four undead body parts fighting the demon, but they were somehow killed (I suspect by being slammed into things enough or were hanging out it one of the surrounding pools when the winter freeze set in).
This whole situation is a pain in the behind for a couple reasons: firstly, thanks to the demon's presence, my baroness won't meet with the dwarven liaison, meaning the county I so richly deserve is off the table, not to mention trade negotiations. Secondly, I find myself constantly having to forbid any items in the area when outside refuse hauling is necessary - which it is when necromancers are in town; gotta atom smash those bones. Third, dwarves have a very punk-rock mentality when it comes to restricted areas, and I'd prefer not to lose any of my boys/new migrants crossing the map to boiling dust.
Some possible solutions:
-Wait for one of them to die, since it apparently is possible, although the demon has only a broken pinky and toe at this point and the skeleton will just not go down. Crossing my fingers for a freeze is another possibility.
-Suicide squad: Possible, although I am skeptical this would work, as the merchant guards didn't even get a hit in before a dust blast took them out. It would require lucky timing and spare dwarves which I don't have (40 of my ~100 are full-time military who I'd be loath to waste, the rest are working pretty constantly)
-Channel out a big square around the battle field, and let the epic battle (if you can call a demon breathing dust at a skeleton who keeps bruising him epic) go on for eternity
Thoughts?