Warhammer 40,000 Dawn of War 4 was recently announced. The developers talked about the fact that at the start they will offer four playable factions: Adeptus Astartes, Adeptus Mechanicus, Necrons and Orks — campaigns will be made for them.
Some fans of the franchise were confused by the absence of Chaos. In a conversation with PCGamesN, creative director Ian Thaysen explained the choice of factions.
Orks: "This is a Dawn of War series game. So the \"Blood Ravens\" should definitely be there. Orks are almost inevitable, especially if you want to go back to Dawn of War 1 in many aspects."
The Necrons were decided to be added because they promised to add them to DoW 3 at one time (this did not happen).
Adeptus Mechanicus — taken partly because the development studio KING Arts previously worked on the Iron Harvest project in a dieselpunk setting.
The team understands the disappointment due to the absence of Chaos — the faction may return in the future:
"We didn't want to: \"Oh, yes, there's also Chaos\" [...] Let's focus on the story about xenos. And who knows, maybe in the future we can do something similar with Chaos."