Horadric Vault: the Complete Collection
Diablo: Horadric Vault, The Complete Collection, published in 2023, is the boxed gathering of the first four Character Tomes: Book of Cain, Book of Tyrael, Book of Adria and Book of Lorath. The US Blizzard Entertainment edition is 9781956916409 and the UK Titan Books edition is 9781803367910, both verified in the census from trade listings.
The box answers the set question in one purchase, and for many shelves it is the sensible form of the tomes: four hardcover style volumes in a shared slipcase, uniform in a way that four separately bought editions across twelve years of publication are not. Cain was first published in 2011 and Lorath in 2023, so individual copies differ in printing history even when their designs match.
One limit needs stating plainly, because the name invites the mistake: the Complete Collection is not complete anymore. Book of Prava, the fifth tome, was published in 2024, after this box, and is not inside it. A shelf that wants all five tomes buys the Vault for the first four and Prava, 9781956916522 in the US edition, separately.
The individual tomes remain in circulation separately as well, with their own ISBNs recorded on their own pages in this Library: Cain 9781608870639 in hardcover, Tyrael 9781608872794, Adria 9781945683206 and Lorath 9781956916140. The Vault's ISBN identifies the box as its own product, so a listing for the box should carry the Vault number, not any single tome's.
No Japanese edition of the Horadric Vault exists. No Japanese editions exist for any of its contents either; the census verified the entire tome line as English only.
