Book of Adria: A Diablo Bestiary

Book of Adria: A Diablo Bestiary is a Diablo-themed sourcebook. In-universe, it is written by Adria as a tome addressed towards the Coven, set before the events of Diablo I. Handwritten notes by Adria within the work are set during events leading up to Diablo III.

The book was originally set for release in October 2018, but was pushed back to November. Physical copies were stated to be available at BlizzCon 2018, while its worldwide release would occur later in the month. The release date was pushed further back to December.

Description
Sanctuary is home to some of the most dangerous creatures to pull themselves from the pits of hell. Tread lightly, and never fall prey to monsters with the Diablo Bestiary. A celebration of the corrupted beasts and grotesque enemies that players have slain across the franchise’s history, this book is the perfect companion to guide you through the next layer of torment.

Trivia

 * The sourcebook was originally simply titled "Diablo Bestiary." In July 2018, its Amazon listing gained the "Book of Adria" subtitle. By September 2018, it was changed to "Diablo Bestiary: The Book of Adria," but had its cover listing as "Book of Adria: A Diablo Bestiary." The article has gone with the cover title.