"No Game No Life" volume 1 by Kamiya Yuu. This is a novel series is about gamers, and this first volume has legends as the main theme. Being the best gamers in the real world will only grant urban legend status, whereas being the best gamers in a fantasy world leads to legendary status and world domination.
Legends and world domination aside, this book is about common games being applied in unusual settings. Two of the games played here were rock-paper-scissors and chess, the first turns out to be a nontrivial game of psychology, and the latter turns out to be an uncanny reflection on the history of warfare. While some people might find these games very silly, the events were expertly written like exciting sports matches. I don't think I will see rock-paper-scissors the same way again.
For people who saw the anime first, the first 4 episodes are an accurate adaptation of the volume 1, minus a few minor details. Reading the novel series might be a bit redundant, although it helps in following the later stories that the anime haven't gotten to yet. The one major feature of the novel is the author's afterword -- the author is an accomplished manga artist was not a novel writer before this work, and the afterword section explained the special circumstances that gave birth to this novel in a very lively way (there is a manga as well, but currently only covers up to chapter 2 of this book).
Well worth reading overall.
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