They don't even appear in the list of dwarves to be selected when forming a military squad.
Don't you have to wait until they became full citizenship to form them in the military?
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Removing their Monster Slayer Labor Location[edit]
It is possible to remove a joined Monster Slayer's Labor Location of "Monster Slayer," effectively turning them into a non-military citizen of your fortress. Simply navigate to the unit, and in their Labor -> Locations tab click the red "X" next to the "Monster Slayer" entry to remove their designation as a Monster Slayer. Upon unpausing, the unit will get a different role based on their highest non-combat skill. They become available for labor and hauling jobs, but are not assignable to a military. It has been observed that they petition for full citizenship at a faster rate after the Monster Slayer role is removed."
or
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How to have monster hunter citizens[edit]
1) Accept long-term residency petition from monster hunter
2) Send monster hunter to another
holding
3) Eventually monster hunter returns, under a different profession
4) Monster hunter will now apply for citizenship two years after return
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dwarffortresswiki.org
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Citizenship[edit]
Long-term residents can apply for citizenship after living in the fort for about two years. Accepting the application will allow labors and occupations assigned to them.
To assign them occupations, the fort-wide occupation they initially had when applying for long-term residency must be unassigned. View the new resident, then select their Labor tab, then their Locations sub-tab, and remove any Location assignments. After this, the new citizens will become available for other occupations.
Mercenaries, monster slayers, and beast hunters will never apply for citizenship, though any other visitor types can become a militia captain after citizenship, effectively making "all-visitor" squads possible.
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dwarffortresswiki.org
