Bestiarum
From Halopedia, the Halo wiki
The Beastiarum is a compendium of information about the various species involved in the Halo games. It is a book included exclusively in the Legendary Edition and Collector's Edition of Halo 3. The book has renders and an grid outline of sorts of the entities of the Halo Universe. It also includes information about the species' homeworlds and the Forerunner Tech Tier. It is written from a Forerunner point of view and cites its sources including communications from The Arrays, The Shields, and 343 Guilty Spark. It is worth noting however that the aforementioned Monitor's observations are "UNDER INVESTIGATION."
