Category: Gear
Price: 25 gp
Weight: 3 lb
Description: Each of these books offers lore about a single combination of creature origin and type, such as fey humanoids. When you fail a monster knowledge check related to a creature with this origin and type, you can reroll the check by spending one hour studying the bestiary. You must use the second result.

Published in Mordenkainen's Magnificent Emporium, page(s) 124.