Deluxe Tunnels & Trolls Hardcover - Rules of Play says:

This is it! The new and improved, Deluxe Tunnels & Trolls. T&T is the second ever fantasy role playing game, and the easiest to use. This book contains everything you need to play the game solo (with the many solo adventures) or with a group of friends. Includes extra material and descriptions of the worlds played in by the original designers!/p>