High-level play (above 20th level) was first introduced in the green-boxed Companion Set for the Basic Dungeons & Dragons game in 1983. Although it was not specifically termed "epic", the rules covered play for characters as high as 25th level. It was quickly followed by the black-boxed Master Set (allowing play up to 36th level) and the gold-boxed Immortals Set (which detailed play beyond 36th level). During this time, what is now called the "First Edition" of the Advanced Dungeons & Dragons game had no support for characters above 20th level.
AD&D Second Edition also limited characters to 20th level, until late in the game's life. In 1996, TSR released DM's Option: High-Level Campaigns, which covered characters in any high-level game and included rules for characters of levels 21-30.
D&D Third Edition first coined the term "epic level" in 2001's Forgotten Realms Campaign Setting in order to account for the unusual strength of many of that setting's many most famous characters. These rules were quite simple, allowing a character to select from a short list of options with each epic level gained. With the subsequent release of the Epic Level Handbook in 2002, an entire system was introduced that allowed for infinite level advancement past 20th level. Each of the base classes was given an epic progression, as were some of the more popular prestige classes. The book introduced epic feats, epic prestige classes, and epic monsters to the game. In addition, it created an entirely new spell system to create epic spells, while still providing options for improving existing spellcasting into epic levels.
When Dungeons & Dragons 3.5 was released, many of the epic rules were included in the Dungeon Master's Guide. Other books, such as Complete Adventurer, Complete Divine, Complete Arcane, Complete Psionic, Complete Warrior and Draconomicon have included additional epic content.
Wizards of the Coast ran a series of articles on their website called Epic Insights which provided additional epic content. It ran from July 2002 through January 2004.
A monster begins to qualify for epic feats once its Hit Dice exceed 20. However, epic monsters generally have access to special abilities beyond the scope of normal monsters, such as the ability to use epic spells as spell-like abilities.
Some epic monsters include:
- Collins, Andy, Bruce R. Cordell, and Thomas M. Reid. Epic Level Handbook (Wizards of the Coast, 2002, ISBN 0-7869-2658-9).
- Gygax, Gary with Frank Mentzer. Dungeon And Dragons Fantasy Role-playing Game Set 4: Master Rules (TSR, 1985).
- Mentzer, Frank. Dungeon And Dragons Fantasy Role-playing Game Set 5: Immortals Rules (TSR, 1986, ISBN 0-88038-341-0).