1) Fictional game 
Jetan, also known as Martian Chess, is a chess-based strategy game with unclear rules. It was created by Edgar Rice Burroughs as a game played on Barsoom, his fictional version of Mars. The game was introduced in The Chessmen of Mars, the fifth book in the Barsoom series. Its rules are described in Chapter 2 and in the Appendix of the book. ==Game...