The Book of Many Things is a sourcebook for 5th-edition Dungeons & Dragons® published in 2024. It focuses on the deck of many things and includes a physical deck of 66 cards and an 80-page The Deck of Many Things Card Reference Guide for using the deck, both stored in a separate box.
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Pick a Card, Any Card
The Book of Many Things reveals the secrets of the Deck of Many Things, one of the most infamous magic items in Dungeons & Dragons. The book explores the deck's divine creator and the undead hunters who want to destroy the deck. Along the way, you'll discover knights who protect those who find the deck, werewolves seeking the deck to lift their curse, and a goblin who uses the deck to read your heroes' future.
This book presents Dungeon Masters with terrifying adversaries, deck-themed locations and traps, advice on introducing and customizing the deck in your campaign, and ways to use the deck to generate encounters and characters. And for players, it holds new magic items, organizations to join, and spells—all inspired by the deck's cards.”
— Back-cover text