Minecraft wiki entry for Game_rule, associated text: When in-game, game rules can be changed using the /gamerule command, using the syntax /gamerule <rule> [<value>], where <rule> is the name of the game rule and <value> is an allowed value, which depends on the type of the game rule. The types are boolean (where the allowed values are either true or false) and integer (where any whole number is able to be entered).