From the update:
We cruised passed the £60k Stretch Goal and unlocked the Guide to the Dark Soul & Apostles - this book is going to be 248 pages (we've unlocked part 1 with 128 pages, the next £6k goal will unlock the extra 120 pages) and is £40 / $64. There will be a later Stretch goal to unlock the colour hardcover upgrade which will be a free upgrade for backers who choose this Add On or have it as part of their pledge.
The Guide to the Dark Soul & Apostles will have a lot of art, tons of never before seen material on the history of the Dark Legion, the origins of the Dark Soul, their previous wars, Pluto, the world of Nero, much more detail on each of the five Dark Apostles, the citadels, the ships, forces, equipment and strategies. No serious Nepharite should be without this book!