In 2004 the license was adapted as "", a role-playing game by Mongoose Publishing under the Open Game License using Mongoose's OGL System. This has met mostly with praise for its adaptation of the Lone Wolf world, though some believe that there are many overlooked problems with the RPG, such as balance between classes and "hard to interpret" rules. Dever is credited with helping the game's principal designer, August Hahn, incorporate information from his final four unreleased books into the game. A line of miniatures was also created for the game.