| Description | My current fortress's 3rd cavern layer is about 80% water, and the first creatures that migrated in from the map edge were blood men. Unfortunately, they migrated into the water, and since blood men can't swim, they got stuck and wouldn't allow anything else to enter.
After editing the blood man raws to permit them to swim, they left the map and were replaced by flesh balls which have been doing the same thing. Even after modding them as well, I've ended up with a group of flesh balls that are content to sit in the water for years without moving a single step, and they're preventing any other creatures from entering that cavern layer.
At several points, I resorted to using a 3rd-party utility to flag groups of sessile flesh balls as "Tame", at which point other creatures began to enter the map; in some cases, the new creatures then attacked the flesh balls, at which point I was able to clear the "Tame" flag and they'd migrate off the map edge. |
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