Are zombies actually killable, err, re-killable?
My first Fortress back in a long while lasted about two seasons before a Human Necromancer Cook (don't want to think how he got started on that career path) turned up with a ragtag army of giblets and bone. I'd picked an "Untamed Wilds" for a starting point so I hadn't really anticipated much competition, but the fort got wiped.
Eventually after about five attempts to reclaim it, I have the fortress up and running. There have been several large goblin armies that have just swept past my fort, apparently heading some place else, various weregeckos and sundry other big critters, but nothing that's really been a problem.
For whatever reason the necro cook showed up again, with another necro in tow, along with a mixed army of undead and elves. The necros have gone their merry way, the elves got stomped by a Cyclops, but the undead are just milling around the corner of the map, occasionally paddling in the nearby brook. Every so often a visitor will show up, excited to find out about this tavern he or she has been hearing about, Depending on which corner of the map they arrive from they either end up leaving thinking the tavern seems a bit quiet, or they get eaten by corpses. It's playing havoc with the tavern's Yelp reviews.
Should I just assume undead are going to be unbeatable in combat and work on some other methods to deal with them?