Core rulebook is a term used to refer to one of the main rulebooks required to play Dungeons & Dragons. It typically refers to the Player's Handbook, Dungeon Master's Guide, and Monster Manual, although the exact books vary between editions of the game.
The term "core rulebook" appeared in Dragon #193 (May 1993), p.120, where it was used to describe the main rulebook of Zeb Cook's For Faerie, Queen and Country (TSR product number 2705), in contrast to that product's "campaign book".
The 1993 TSR Catalog, page 16, refers to the Book of Artifacts (1993) as a core rulebook with a guaranteed market. The book is described as "an essential element of the core rules to the AD&D game system". However, this marketing copy is misleading, as page 4 of Book of Artifacts describes it very specifically as an optional supplement:
- "The Book of Artifacts is a supplement for the core rules of the AD&D® 2nd Edition game. In other words, everything in this book is optional. This is not something every DM must have or a book every player should read. DM's who want to use the material here can, others don't have to. The Book of Artifacts is not a vital piece for every campaign."
This early usage begins to solidify the concept of "core" rulebooks as those vital to play Dungeons & Dragons.
D&D 3rd edition
The term "core rulebook" was not widely used until Dungeons & Dragons third edition, which used the term to help new players to identify which books were required for play, as opposed to the later optional expansions. Text on the cover of the Player's Handbook (3.0) (2000), Dungeon Master's Guide (3.0) (2000), and Monster Manual (3.0) (2000) identified them as Core Rulebook I, II and III, respectively.
Later editions of the game continued to use the term "core rulebook".
Dungeons & Dragons 4th edition's Player's Handbook (4e) (2008), Dungeon Master's Guide (4e) (2008), Monster Manual (4e) (2008) were identified on the cover by the text "Roleplaying Game Core Rules", although the books are no longer numbered. The Dungeon Master's Guide refers to the term "core rulebooks".
Dungeon & Dragons 5th edition's Player's Handbook (5e) (2014), Dungeon Master's Guide (5e) (2014), and Monster Manual (5e) (2014) no longer refer to themselves by the term "core rulebook". However, that term is still used to refer to those books. For example, Xanathar's Guide to Everything (2017), p.4, described as the first major rules expansion for D&D 5th edition, states:
- "Nothing herein is required for a D&D campaign—this is not a fourth core rulebook—but we hope it will provide you with new ways to enjoy the game."
Editions of Dungeons & Dragons prior to third edition did not use the term "core rulebooks", but the concept of certain rulebooks as necessary for play certainly existed during the TSR era, and the term is sometimes retroactively applied to refer to those books.
The original Dungeons & Dragons game was released in a three-volume set: Men & Magic (1974), Monsters & Treasure (1974), and The Underworld & Wilderness Adventures (1974). This set is usually referred to as the "White Box" rather than "core rulebooks", although that term could arguably apply.
The various editions of Basic D&D did not use a three-rulebook set, and the term "core rulebook" is not consistently applied.
Advanced Dungeons & Dragons 1st edition pioneered the three-book set of Monster Manual (1e) (1977) Players Handbook (1e) (1978) and Dungeon Masters Guide (1e) (1979). In practice, books were released a year apart due to production difficulties and many players would mix-and-match AD&D and earlier OD&D content.
Both Advanced Dungeons & Dragons 2nd edition and its revised edition referred to the term "core rules", but declined to strictly define any particular combination of books as canonical. Those editions also did not use a Monster Manual, using the Monstrous Compendium series and later the Monstrous Manual. The Player's Handbook (2e) (1989) and Dungeon Master Guide (2e) (1989), and later the Player's Handbook (2e revised) (1995) and Dungeon Master Guide (2e revised) (1995) could be considered core rulebooks.
- Dungeon Master's Guide (4e) (2008), p.141.
- Dungeon Master Guide (2e) (1989), p.3.