Howdy Akira buddy!
Exciting to see more material published.
Yes its about time.
Text wise how much lore will be packed into these two books?
As much as possible*, though I am starting to get a bit self-conscious about the page count going over 400 pages.
I don't want the book to become unwieldy at the table (if that makes any sense).
*That said, there are about 20 stat-blocks in the book (some sample immortals for either Purviews or Divine Ranks and others summoned by Epic Spells) and I have condensed to 2 pages (including 1 page for the art). So its a short write-up + Lore (I folded the Lore and Adventure Ideas into the same thing) + Realm details in one column and then the stat-block in the other column.
But in the Bestiary, named immortals with Realms and 'big' monsters will get 4-page treatment rather than 2.
I really enjoyed the plot Hooks on the bestiary and the flavor texts for the IHB.
I think aside from the rules themselves (this book is basically a simplified 5e Ascension + Grimoire + Gods & Monsters all rolled into one) the big new 'thing' is the new dimensional structure. Which has some new dimensions and all the 'old' dimensions from 3.5E are split into two (along a Michael Moorcock law-chaos style split).
ie. Kuvachim is the 8th dimension which you all know as the Diamond Heaven, basically an infinite diamond wall where every facet is a different multiverse. But now there is also its counterpart Bohu, which are the black facets on the wall. These are dead multiverses. Except that all the black facets lead to the same nasty place. So its a sort of cosmic chess game where diamond and black 'pieces' battle across an infinite playing board.
Space being at a premium and this being a Player's Guide, not a Setting Guide, I can't detail these dimensions more than a handful of paragraphs. Plus I know if I try to add more pages the whole thing will snowball into another chapter and I would rather save that for another book.
Obviously Epic Bestiary 1 (with 100+ Epic Monsters) will detail monsters from some of these realms and dimensions (again as space allows).