ok im back and now its time to discuss the ideas thus far, this is going to be a very long post...
Firstly Dwarf Kitty stated the following in his post:
Jumping into this.
You know how some legendaries in worldgen strive to extend their lives by any means necessary, then become vampires and such? They gotta figure those things out somehow. What if the Revenant civ is an alliance of like-minded cults and cultists?
The base race are living souls who seek the darker magics. Embrace death and become necromancers, extend life indefinitely through vampirism or lichdom, or raise the Carp God. Loosely allied, they find safety in numbers. Even the drow distrust them. (Challenge: Create a civ that contains representatives from the other races.)
Their pets are anything from shades and ghosts (humanoid as well as ghost dogs and kitties) to Lovecraftian deep one abominations.
Citizens must study to become or be transformed into supernatural creatures, such as vampires and werebeasts or lichs. (Think the transformations of the golem forge or the Masterwork temples.) Anything that comes from the living and still has a semblance of life.
The cultists have sacrificed the ability to reproduce naturally, either as a vow of celibacy or enforced through more macabre means. Reproduction (to answer Isngrim's question) would then be through recruitment or conversion. Migrant waves would be of fresh recruits or converts. Any invaders captured would be either converted or sacrificed.
Fallen untransformed citizens and fallen invaders could be ressurected as zombies or part-zombie convert slaves. Ideally, these become citizens, but pets would work well enough if the other reproduction avenues are in place.
Also, corpse bone and flesh and blood would be important materials. Maybe sanctify their weapons and armor? Give the butcher shop or slaughterhouse an "extract blood from fresh corpse or victim" reaction, then use bone and blood as reagents in forging.
The soul shard would have to be harvested easily if you're going to require them for items. Perhaps a certain type of mage would take a sentient being's corpse and magically distill it down into a crystal. If the soul distilled had already become a ghost, the ghost disappears as if memorialized. Or the shard is dropped from some corpse-munching animal like the golden goose drops gold bars.
Ooh, idea: Revs create special dark glass for various uses, take raw dark glass and sentient being's corpse to make soul shard!
And I vote that blood or bone meal is the special ingredient to make dark glass.
The ideas above are very good and i like the idea that bone and blood would be important for the faction in question those being the revenants, thus I have adopted the usage of those into the mod (I have a supprise coming for you guys shortly
).
Not over keen on the like-mindedness with the carp god cult BUT I will have the cult playing a slight part in the revenants for alternateive reasons Hehehe.
The pets idea sounds good but i was not thinking on lovecraftian monsters but more on the line of bone golums (large monster created from at bare minimum 60 bones[wait intill my next post, you might like the methods of getting said resources]) and (much later) Death pact ( large constructs that can take an ungodly ammount of damage and can be merged into a squad[civilian transformation]) but ghostly animals could be a possibility.
You touch on my idea of civ transformations in your 5th paragraph.
Loss of reproductive organs would cause them to die at world gen I think *correct me if im wrong*
I am planning on have a building at teir 1 that allows migrants to be summoned but it will be VERY expencive but I will also have a use for said migrants (yes im talking to you legendary + 5 beekeeper >
)
dead civilians becoming slaves? Dfhack i think but im useless with Dfhack gamerlord MIGHT know more about it then I do but thats up to debate.
Soulshards WILL be used BUT not from that method, I have a slightly better way of aquireing them and you guys might like it
Now for the ideas posted by somebears, no seriously some bears just told me this its a bit crazy I know hehehe (dont hit me!)
I am very pleased to see that you are going down a teir route for your suggestions, this makes it easier for me and gamerlord to see where you want the suggestion to be on the list of buildings and teirs HOWEVER as gamerlord stated, most of your ideas will need Dfhack somthing that I dont fully understand in the slightist.
but on a possitive note their will be reactions to trans a caste to another caste but that is only if the castes work D:, speaking of this Gamerlord please update me on the civ files I need to PM you about them.
you also talk about some castes being able to do some things better then others, thats also exactly what im goiong to be doing too but on a different level.
Now be right back, typing my massive page now for my main ideas AND todays to-do list for me.