Dungeons & Dragons retro-clones

Dungeons & Dragons retro-clones are fantasy role-playing games that emulate earlier editions of Dungeons & Dragons (D&D) no longer supported by Wizards of the Coast. They are made possible by the release of later editions' rules in a System Reference Document under the terms of the Open Game License, which allow the use of much of the proprietary terminology of D&D that might otherwise collectively constitute copyright infringement. However, per the license, these games lack the brand names Dungeons & Dragons, D&D, and all the other trademarks associated with those brands.