Раскрытые Арканы: Дополнение к Dungeons & Dragons от Гэри Гайгекса

AD&D supplement by Gary Gygax

Unearthed Arcana (abbreviated UA) is the title shared by two hardback books published for different editions of the Dungeons & Dragons fantasy role playing game. Both were designed as supplements to the core rulebooks, containing material that expanded upon other rules. The original Unearthed Arcana was written primarily by Gary Gygax, and published by game publisher TSR in 1985 for use with the Advanced Dungeons & Dragons first edition rules. The book consisted mostly of material previously published in magazines, and included new races, classes, and other material to expand the rules in the Dungeon Masters Guide and Players Handbook. The book was notorious for its considerable number of errors, and was received negatively by the gaming press whose criticisms targeted the over powered races and classes, among other issues. Gygax intended to use the book's content for a planned second edition of Advanced Dungeons & Dragons; however, much of the book's content was not reused in the second edition, which went into development shortly after Gygax's departure from TSR. A second book titled Unearthed Arcana was produced by Wizards of the Coast for Dungeons & Dragons third edition in 2004. The designers did not reproduce material from the original book, but instead attempted to emulate its purpose by providing variant rules and options to change the game itself. The title Unearthed Arcana is also used for a regular series on the official Dungeons & Dragons website that presents new playtest content for Dungeons & Dragons fifth edition.

The original Unearthed Arcana was written by Gary Gygax with design and editing contributions by Jeff Grubb and Kim Mohan, respectively, and published by TSR in 1985. Gygax reportedly produced the book to raise money as TSR was deeply in debt at the time. He announced in the March 1985 issue of Dragon magazine that Unearthed Arcana would be released in the summer of that year. He proposed the book as "an interim volume to expand the Dungeon Masters Guide and Players Handbook", as the information was spread out in several places and difficult to keep track of. According to British writer Paul Cockburn, some of the material in Unearthed Arcana had been previously published in Imagine magazine. Dragon editor Kim Mohan, with ideas from Gygax, Frank Mentzer, and Jeff Grubb, addressed the many errors found in the book. In the November 1985 issue of Dragon magazine, Mohan printed four pages of rules corrections as well as new supplementary material intended to be inserted into the book, and some explanations and justifications for items which were not actually errors, and compiled a two page list of type corrections meant to be pasted into further revisions of Unearthed Arcana. Dragon also devoted the entirety of its "Sage Advice" column in the January 1987 issue to answering readers' questions about Unearthed Arcana, as a follow up to Mohan's prior column. However, the errata were not incorporated into later printings of the manual. Wizards of the Coast reproduced the original Unearthed Arcana in a premium edition featuring gilded pages, released on February 19, 2013, following the premium reprints of the original 1st Edition Player's Handbook, Dungeon Masters Guide, and Monster Manual. This reprint is the first printing of the book to be modified with the errata previously published in Dragon magazine incorporated into the corrected text.

The 128 page Unearthed Arcana was written for use with the Advanced Dungeons & Dragons first edition rules and was divided into two sections: one for players and one for the Dungeon Master (or "DM", the game organizer). The book provided new races, classes, and other expansion material. The book gives details on using "subraces" of the standard races, such as dark elves (drow), and deep gnomes (svirfneblin), for use as player characters and non player characters. Unearthed Arcana includes the barbarian (found in Dragon #63), cavalier (found in Dragon #72), and thief acrobat (found in Dragon #69) character classes, Gygax used his work on the book to explore ideas for the new edition, such as changing the mechanics for hit dice (the measurement of a character's "health" in the game), and changing the mechanics to allow the game system to work with other genres, and to allow characters to have skills that complement the character classes. Shortly after announcing his intentions for second edition, Gygax was removed as TSR's president and chairman of the board. In 1986, he resigned entirely from TSR, leaving further direction of Dungeons & Dragons to other designers. The designers of second edition Advanced Dungeons & Dragons removed material from the original Players Handbook in the new edition, as well as much of the new material that had appeared in Unearthed Arcana, which they considered to be "unbalanced". The book had five printings after the release of AD&D 2nd edition with the last printing published two years after the new edition was released.

The second book to use the name Unearthed Arcana was written by Andy Collins, Jesse Decker, David Noonan, and Rich Redman, and published in February 2004 by Wizards of the Coast, for use with the Dungeons & Dragons third edition rules. and to think before using options that may radically imbalance the game. The book ends with a checklist of the included variants, preceded by a short chapter discussing ways of transitioning among multiple games using different rulesets (one of which explicitly emulates the "Eternal Champion" stories of Michael Moorcock).

The Unearthed Arcana title has been used for a semi regular series of digital releases at the official D&D website that began in February 2015; the series presents new, work in progress content such as class archetypes, playable races, and rule variants, similar to the playtest process that preceded the release of 5th edition. Much of the information in Xanathar's Guide to Everything (2017) On the playtest subclasses developed for Tasha’s Cauldron of Everything, Jeremy Crawford said "almost every single one made it into the game". Once the playtest period has concluded for Unearthed Arcana content (whether it is published in a book or retired, as determined by Wizards of the Coast), it is archived on D&D Beyond; existing character sheets already using the content are able to continue doing so, but the archived playtest content can not be newly added to a character. In August 2023, Crawford stated that since originally launching Unearthed Arcana they have "received more than 500,000 surveys from players based on their time spent with the" playtest content.