Finding decent info on the Daevites is pretty difficult so if you have anything and links to it pop them here.
No SCP 6140 stuff. "They were actually boring all along and all this interesting stuff is just revisionist history" is just boring among other things.

Currently already aware of:
SCP 3140 -> Tree mechs. Will be added as a men at arms, plus maybe a court position for someone in charge of taking care of them which improves their quality.

SCP 140 -> History-rewriting book that adds more history to the Daevites - changing actual history as it does so - when it gets more ink or blood. Won't be implemented. The book either ends when the Daevites are wiped out in the game or at some point after you stop playing if they aren't.

SCP 4008 -> Seeds that not only destroy entire cities and wipe all memory of them and those in them from the collective human consciousness. Your enemy doesn't even notice and so won't retaliate after you destroy one of their urban centers honestly seems like an even bigger advantage than the 12 meter tree mechs. Casus belli that you instantly win, turns the target county into an independent worthless (awful modifiers) garbage heap that nobody should want to rule.

SCP 3399 -> Tree whose seeds are used for mapping out potential offspring and their genetics. Used for selective breeding of humans and Daevas among the Daevites. Implemented as an artifact, but trying to add a character interaction that requires you to have 3399 that gives a modifier improving the genetic outcomes of children.

SCP 4824 -> Turns out Daevites don't like homosexuality, at least not in men. Given that it's a society where your job is either being a slave or helping to oppress / acquire slaves or both this makes sense, as making more oppressors or slaves would be considered a duty. A modifier somewhere of this funky storm, maybe also a decision to go and meet 4824.