Using rejuvenate successfully changes dwarves to 20 in fortress mode; however, retiring the fort and checking the dwarves in Legends Mode will state they were born in their original birth date. Reclaiming the fort will show they are all, however, still 20 as I left them.
Rejuvenate on Adventurer Mode will appear to work on a never-before-retired character, giving the message that <name> is 20 and will live at least a hundred years, but retiring them will show they were born at some other completely different time, and attempting to use rejuvenate on a previously retired character, who thus already has an age set in legends, will just crash the game.
Why? I realize this function wasn't intended for Adventurer Mode, I am curious though.
Does the supposed birth date actually matter? If I remove the birth date change and make rejuvenate only use unit.old_year = current_year + 100, would that work fine? It'd take a lot more time investment for me to check this part myself.
I understand rejuvenate isn't meant to be used in Adventurer, but does anyone know how it might be used that way? Taking the function and only slightly changing it lets you put in any number into the argument so you can pick the age of the target, I tested this with 20, 34, 15, and 9, and stuff changed just fine, retaining it. If something along these lines could be used to customize your adventurer's age, that'd be nice. Maybe it'd have to be something done on the setup screen, much like adv-max-skills, though in this case to avoid crashes and make it stick in legends mode (I would hope).
Any input would be appreciated, I don't know how anything works.