The Calamity Boon is a game played by the former champions of The Orange and Steel.
The rules of the game are simple, conquer all the worlds and kill all the other champions. Every champions starts in a different world, recovering from a catastrophic event. The champions mobilize local forces to conquer the other worlds, they battle the other champions in duels.
When a champion dies he is removed from the game, reborn on a world without Gates, left to watch the unfolding of the rest of the game.
The name is of the game refers to it being a Boon to the champions, something to pass the time for eternity, and the Calamity is what is visited onto local populated, leaving them devastated after every game.