You may be looking for the original website manuscript.
For the lore book and in-game object, see Book of Cain and Book of Cain (Diablo III).

Deckard Cain's Journal is divided into two parts, both of which can be found on Cain's desk in Act I of Diablo III. Retrieving them adds to A Quick Study achievement.

The parts read as follows:

Part 1Edit

Part 1 is unlocked with The Fallen Star quest.

We have come at last to Tristram's old Cathedral. This is where Diablo, Lord of Terror, first corrupted mankind. This is where I may finally find the answers I seek. Leah worries after my safety, but I believe information vital to defeating the last lords of the Burning Hells can be found here.

Part 2Edit

Part 2 is unlocked with the Reign of the Black King quest.

I wish that Leah could live a different life--a more normal life--but, alas, such is not her fate. When I pass, there is none but her to continue my work, and the future of this world hangs in the balance.

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