In the event I were to tinker with the new features to add more magic secrets, is immortality still the only motivation that'd cause the secret to be learned in worldgen? Or has anyone been able to get other existing motives to work successfully?
I think the new update added some goals related to the villain additions:
https://www.reddit.com/r/dwarffortress/comments/ex4ayg/found_this_dwarf_in_my_starting_seven_is_his_goal/ . However, I don't think anyone has gotten any other goals to drive acquiring secrets and there hasn't been any devlogs by Toady indicating he added other goals to secrets (presumably this would be a big enough change that he would at mention adding it). I can't find the place I saw, but I remember that someone had found (or maybe Toady mentioned), that Necromancer's can gain an additional goal that drives them to conquer the world, but this is after they are necromancers so I don't think it drives secret acquisition?
That said, if you are looking for secrets to be added to the world, you could use the modding method used in Spellcrafts mod (
http://www.bay12forums.com/smf/index.php?topic=149426.0). They gave several creature the SPHERE alignments and the SUPERNATURAL token, and then made many secrets with the IS_SPHERE tag and the SUPERNATURAL_LEARNING_POSSIBLE to let these creatures learn the secret and then MUNDANE_RECORDING_POSSIBLE to generate slabs and allow them to record it and MUNDANE_TEACHING_POSSIBLE so they would pass on the knowledge. This was in 44.x, presumably it will work in 47.x, and might even work better? I've been thinking of testing out if the new villainous networking and exchange of secrets as bribes will propagate secrets that originated this way.
DEMON_UNIQUE is RAW usable in 47.x, so presumably the same approach could be used to propagate secrets through the demons that lead other Goblin civilizations. Maybe it will also work for intelligent megabeasts that become deified in civilizations? It isn't possible to give other civilizations demon leaders yet without adding Dark Towers as their starting site type and allowing VARIABLE_POSITIONS:ALL, which causes crashes if you also have RAW defined entity positions.
I suppose doling out immortality, especially if it was JUST lack of aging rather than all the other side bonuses necromancy normally grants, would be adequate if it was still essential to prevent teachings from dying out before they can be passed on...
I think immortality is needed to drive them out of their home civilization.
Does anyone know if IS_SECRET_GOAL:IMMORTALITY will work even if the secret doesn't actually grant immortality? I suppose I will try testing this also if no one knows...