Example image of eyePlorer eyePlorer map for 'D20 System': 2000 Dungeons & Dragons Role-playing game system Wizards of the Coast Dice Open Game License Open gaming System Reference Document Brand management Network effect Jonathan Tweet Monte Cook Peter Adkison Richard Baker (game designer) Skip Williams Ars Magica Armor class Saving throw GURPS Basic Role-Playing Chaosium Role-playing game Deities & Demigods Dungeon Master's Guide Expanded Psionics Handbook List of Dungeons & Dragons rulebooks Monster Manual Player's Handbook Campaign setting Greyhawk Illithid D20 Modern D20 Future D20 Menace Manual Urban Arcana Electronic publishing Censorship Skirmisher Publishing LLC Typeface Conan the Barbarian Robert A. Heinlein Starship Troopers 7th Sea (role-playing game) Alderac Entertainment Group Legend of the Five Rings Offset printing Print on demand Kenneth Hite Advanced d20 Magic Darwin's World