A trailer for Total War: Warhammer 2 - Mortal Empires has been released by Sega, and developer Creative Assembly, ahead of it's PC release on the 27th of October (in NZ).
Mortal Empires, a massive free expansion to owners of both Total War: Warhammer & Total War: Warhammer II (requires ownership of both games to play), contains the following content:
Additionally, according to the DLC's Steam Page, unlike the campaign that shipped with Total War: Warhammer 2, Mortal Empires doesn't focus on a single story.
Instead, it offers the classic sandbox Total War experience in the Warhammer Fantasy Battles world, expanding your empire in any direction you choose with no limits. You’ll still experience the escalating Chaos Warriors invasion from the original Total War: WARHAMMER Old World campaign, but with an exciting new twist: the forces of Chaos don’t just attack from the Chaos Wastes, but from other, unexpected directions as well...
The content is also a "bespoke new campaign map", and not an exact copy of the Total War: Warhammer 1 or 2 campaign maps, which means some factions have unique new starting positions. "The Skaven warlord Queek Headtaker of Clan Mors, for example, begins with ownership of Karag Orrud in the south-eastern Badlands. This puts him in the heart of Greenskin territory in the Old World."
The Steam page also mentions that the The Norscan factions won't be available until a free update later this year, which will increase the Legendary Lord count to 37.
Total War: Warhammer 2 - Mortal Empires releases on October 27, 2017 to PC via Steam.