Mostly to remind myself to keep working on a repository of seraphon fluff, but this is a summary of all the explicitly new fluff from the latest parts of the refresh (with the caviat that its from WH community posts and livestream stuff, so not guarenteed to be 100% accurate to the future battletome):
*Aggradons are beasts blessed by Itzl, the old one who presides over cold-blooded beasts (and who's blessing was required for a skink or saurus to be capable of riding a Horned One in WHF). Their eggs laid dormant in Ziggurats of Itzl for millennia, possibly since the collapse of the polar gates in the old world, but have been reinvigorated and begun to hatch with the wave of ghurish energies engulfing the realms after Alarielle's rite of life threw the realm into a frenzy. Raptadons (skink cavalry) appear to have the same backstory, though it's not been explicitly mentioned that their eggs were also in the Itzl ziggurats and was implied they were just generally around in the temple-ships instead.
-As a note on the Ziggurats of Itzl, In WHF Itzl's temples were isolated structures in the lustrian wilds, far from civilization, and honored by skinks that lived beyond the walls of temple-cities. It's possible (even likely) that many of these Ziggurats of Itzl mentioned to house Aggradon eggs were one in the same with those temples of itzl, just having escaped the planet alongside the temple-cities and other old-one monuments that were built with that failsafe mechanism. Given new temple-ships, spawning pools, etc can be built by Seraphon in AoS (via mechanisms within each major temple-ship that can build and "bud" the varying structures and temples attached to them) they're probably not all relics of the old world, but if Aggradon are a previously extinct species from the Old World then most that have their eggs would be.
*Kroxigor Warspawned (the more crocodilian form) are Kroxigor blessed by sotek, and carry the normal heightened aggression and defensive instincts that skinks and saurus with the same blessing have. Unlike sotek blessed skinks and Saurus, however, Warspawned Kroxigor are living weapons that exist only for war and can barely function outside of it, unable to feed or clean themselves like even normal Kroxigor are capable of. They rely entierly on dedicated skink attendants to take care of them, otherwise they'd just starve to death, and this creates an even closer bond between them and skinks than the normal one shared by the two species. Warspawned aren't a new subspecies, but prior to the era of the beast and the glut of warfare/awakening of stronger warlike instincts in the seraphon they were so rarely spawned (presumably existing in their miniscule numbers even back to the old world) that they had no real presence in the armies or plans of the seraphon, though now their numbers swell with sotek-blessed spawning after sotek-blessed spawning occuring as the era of the beast marches on.
-A little note on these guys is the crocodile influence seeming at odds with what sotek's blessing usually gives to saurus and skinks (snake-like traits and split tails), but I figure on top of giving an option for total-war style designs, them being a sotek-blessed subspecies probably references the Crocodile headed egyptian god Sobek that a lot of people suspect is the origin of the name Sotek.
