From the introduction:
In 1972, Lord Ryar Lyakizan created the most famous of all table-top RPGs, “Castle and Caves”. People use books, pen, paper, funny-looking dices, and their imagination to play this fantasy medieval role-playing game. One of the most famous players was Arthur Lionheart, who was a head of Merlin Magic Inc., a recent company trying to break into cartoon — but mostly had been doing cereal commercials — much to Lionheart’s dismay. Lionheart liked, “Castle and Cave”, but was worried that they won’t allow some to mess with the major world, ‘Greenskill” and its citizens. They talked to Lord Ryar’s company, BTG (Battle Time Games), about the table-top game. Ryar and Arthur got a long just fin, and Arthur was right — but Lord Ryar stated “Sorry about that, but that’s life on terra firma.” Terra firma means “dry land” — but Arthur got an idea to use Terra has his setting.