Preview article on FEC lore is up:
I'll have some updating to do for my big undead lore pile, including updating some second edition stuff, as the new book retcons in some lore for Ushoran during the soul wars - discovered in Ghyran by agents of Neferata, re-imprisoned by Nagash in a great bone palisade, only for that wall to crumble and let him back out after Nagash's fall and Alarielle's Rite of Life.
We also seem to have an Ushoran who is fully loyal to Nagash and his fellow mortarchs, at least so long as his delusions hold, but with hints that he might be plotting to undermine them in his more lucid moments, which leaves some nice room for intrigue.
As one would expect the FEC courts have taken to the Age of Beasts better than most other undead factions thanks to Mordants not being truely dead and thus being energized rather than suppressed by Alarielle's Rite of Life. Again, this was expected going into 3rd edition. It's a shame they're really only getting into it now in the build up to 4th edition, but I don't think the transition from 3rd to 4th is going to see the same sort of major shake up to the cosmology that we saw in the transition from 1st to 2nd or from 2nd to 3rd.
From what I can tell, the (temporary) defeat of Nagash & Arkhan, ascention of Morathi, escape of Kragnos, and surge of Life Magic will still be the dominant influences on the overall setting in 4th edition. Maybe the writers will even remember that Be'Lakor cut off access to the entire Realm of Metal and spread a shroud of darkness across the space between the realms? That was kind of a big deal, but seems to have been largely forgotten by the narrative. Anyway, I expect the main change from 3rd will be pulling the focus back to look at how the other Realms have been reacting to these events, where 3e was focused tightly on just the Realm of Beasts.
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EDIT: Also, I miscounted existing warscrolls when checking if there might be further changes, in that I left out the new herald hero on account of he's still not in the app. That means if we count all the existing scrolls plus the new ones, we're actually one over on total number of warscrolls, so at least one current unit is getting dropped and/or folded into another unit. IMO likely options include:
1. regular ghoul courtier could be dropped / folded into the herald
2. infantry ghoul king and archregent could be folded together.
3. Duke Crackmarrow could be part of the Grymwatch instead of a separate warscroll.
4. The charnel throne faction terrain might just be dropped. It never looked very good and has been perpetually out of stock pretty much since it came out. EDIT: Battle report on warhammer tv confirms Charnel Throne is still a thing.