The Age of Darkness Rulebook is coming Friday from Foreworld and if you do not recall, is still using the 7th Edition ruleset, with modifications from community feedback.
via Forgeworld
https://www.warhammer-community.com/2017/10/30/the-horus-heresy-rulebook-pre-order-on-friday/
Get ready to return to the 31st Millennium with the new Horus Heresy Age of Darkness Rulebook, available to pre-order this Friday. This book is your guide to gaming in the Age of Darkness; this valuable resource is for both experienced Praetors who’ve been playing since Betrayal and fledgeling Consuls looking to take their place in the greatest war the galaxy has ever known.
We know some of you want to know exactly what the Horus Heresy Age of Darkness Rulebook is, so we’ve prepared a quick Q&A:
What can you tell us about the upcoming Horus Heresy Rulebook?
It is a rulebook for use with the Horus Heresy range of miniatures using the 7th edition ruleset.
The core of the rules will be familiar to those playing the Horus Heresy today, but there have been some changes. Can you tell us about any?
The previous FAQs for 7th edition have been incorporated and the army construction section uses the Horus Heresy rules instead of the 7th edition standard. We’ve also made some balance changes based on community feedback. Invisibility has been replaced, while the usage of melta-bombs has been changed.
Does the new book work with the current range of Horus Heresy books and expansions?
Yes – all your red and black books still work!
What is in the book apart from the core rules themselves?
The rulebook just contains the core rules and useful reference material – you’ll find all the lore and specific rules for your chosen Legion (or the Mechanicum, or Crusade Imperialis) in the various Horus Heresy supplements.
In short, if you’ve been playing with the 7th edition rules then the game is much the same as it always was, but for some much-asked-for balance tweaks and less bookkeeping thanks to integrated army creation rules and FAQ updates. For instance, Invisibility with the new Mind Howl psychic power:
