Elminster's Candlekeep Companion
Elminster's Candlekeep Companion is a 3rd party splatbook for Dungeons & Dragons 5th Edition from the DM's Guild that seeks to expand the Forgotten Realms setting by focusing, as its title suggests, on Candlekeep; the massive fortress-library on the Sword Coast made famous as the childhood home of your player's character in the legendary Baldur's Gate Duology. Seeking to be a definitive guide to Candlekeep, it also includes the first ever attempt at creating a comprehensive map of the fortress-library in its entire history as a D&D element.
The book itself consists of 6 chapters, plus a short introduction that provides 5 essential facts to understand about Candlekeep and a short history of the fortress-library.
Chapter 1: Player Options
The book begins with four new sublasses for players.
The College of Destiny for Bards is a bardic archer whose subclass features revolve around prophecy and manipulating fate.
The Prophecy Cleric Domain is for clerics who strive to see, understand and even control the future. Like the Oracle from Pathfinder, clerics who take this domain must take one of several flaws in exchange for their diviner-like array of subclass features.
The Way of the Avowed Preserver is the obligatory "Candlekeep Monk" class, representing the mystical fighting style developed by the Avowed to protect Candlekeep from those who would destroy it.
Finally, the Academic Lore tradition for wizards is an attempt to create a fresh slant on the "generalist wizard" that hopefully isn't as humiliating to the sorcerer as the Loremaster from Unearthed Arcana.
Chapter 2: The Library Fortress
This chapter presents a general overview of Candlekeep, such as requirements for entry, major locations, and expanded details the monastic order known as the Avowed, the custodians of Candlekeep who represent a syncretic alliance of the faiths of Oghma, Deneir, Milil and Gond.
Chapter 3: The Great Library
This chapter is a more in-depth look at the Great Library of Candlekeep, focusing particularly on its rules, and the books contained therein.
Chapter 4: Candlekeep Adventures
As the title suggests, this is all about adventures relating to Candlekeep, whether the players come here from elsewhere or find adventure within the walls! Subchapters are also devoted to the famous Prophecies of Alaundo and ties into the official adventure "Descent into Avernus".
Chapter 5: Magic Items and Spells
The title of this one says it all. Naturally, there's a big focus on magical books, tomes and grimoires.
Chapter 6: Friends and Foes
This bestiary chapter is divided into two subchapters: The first section is devoted to new monsters; these consist of the Glowglobe (an animated glowing crystal ball meant to provide a safer alternative to candles), Tome Guardian (a scholarly earth elemental covered with transcriptions from its favorite books), the Bookworm (a magical and dangerous version of the traditional library pest), and Miiyrm, the Sentinel Wyrm (the ghost of a Silver Dragon compelled by magic to defend Candlekeep).
The second section is an assortment of new generic NPC statblocks; the Seeker, the Renowned Scholar, the Bard of Destiny, the Cleric of Prophecy, the Avowed Preserver, and the Loremaster Wizard. All four of the latter statbllocks are NPC versions of the subclalsses introduced in the first chapter.