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Monsters of Faerûn features 96 pages of monsters unique to the Forgotten Realmscampaign setting. It was the first 3rd edition book to feature the now-common "in the Realms" section for each monster, offering helpful and concise hints to the Dungeon Master as to how and where to incorporate the creature into the campaign setting.
The reviewer from Pyramid stated that "Dungeons and Dragons has long had a tradition of making a lot of Monster Compendiums, a showcase of new and exotic monsters to add to the creatures in the Monster Manual, for settings from the Forgotten Realms to Dark Sun. The first Monster Compendium made for the Third Edition of Dungeons and Dragons continues this old tradition, and does it well."