Diablo II: To Hell and Back
From Diablo Wiki
This roleplaying game module is a supplement to Diablo II: Diablerie released as part of the Dungeons & Dragons 3 ruleset.
The book contains quests, adventures and monsters as well as rules for hirelings (the Rogue, the Desert Mercenary and the Ironwolf). It's possible to play this module without Diablerie, but more Diablo world gameplay is available when using both.
Unfortunately, the book was not very well received by fans, and is primarily referenced to as a decent book "for D20 system monsters" as it contains a lot of monsters from Diablo II.
This is what RPG.net has to say about it: 
- A super-dungeon-crawl for use with the Diablo II rules for D&D. Includes every level level and all four acts of the computer game.
- Notes on This Edition
- 192 pages.
There is a Secret Cow Level for the roleplaying game as well:
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