The Multiversity Annotations, Part 6: The Guidebook
The sixth issue of the series, Guidebook, while certainly the D&D-style sourcebook of the event and a guide to Morrison's vision of the DC multiverse, is also a necessary section of the overall story, answering many questions and asking others, as well as providing the introduction of the Empty Hand, the series' true villain and master of the monstrous Gentry.
It's structured as stories within stories --- Marcus To draws a segment with Li'l Batman and Atomic Batman on Earth-42, while Paulo Siqueira illustrates the New Gods, Kamandi and the history of the DC Multiverse in an intercut sequence taking place on Earth-51. Both of these stories intersect with pages from the Guidebook itself, designed by Rian Hughes with illustrations by a large number of artists.