The Horus Heresy Rulebook goes on preorder Friday. https://www.warhammer-community.com/2017/10/30/the-horus-heresy-rulebook-pre-order-on-friday/ It is basically 7th Ed. with some modifications for HH play, so all your Black and Red HH game books are still valid. And all done with the style we've come to expect from a FW HH book.
The new Horus Heresy: Age of Darkness Rulebook is...... Delayed after a print quality check! (Damn printing Servitors!) https://www.warhammer-community.com/2017/11/03/horus-heresy-age-darkness-rulebook-delayed/ As a consolation you can download a free wallpaper from The Battle for Prospero!
Warhammer Community, FW Preview: Varagyr Terminators of the Vlka Fenryka. https://www.warhammer-community.com/2017/11/06/forge-world-preview-varagyr-terminators/
Age of Darkness Rulebook, £40. https://www.forgeworld.co.uk/en-GB/The-Horus-heresy-Age-of-Darkness-Rulebook-2017
