Historical Rules · 27 September 2013
Rule 112.6m
Official source text from the 27 September 2013 Rules release
An ability that modifies the rules for deck construction functions before the game begins. Such an ability modifies not just the Comprehensive Rules, but also the _Magic: The Gathering_ Tournament Rules and any other documents that set the deck construction rules for a specific Constructed format. However, such an ability can't affect the format legality of a card, including whether it's banned or restricted. The current _Magic: The Gathering_ Tournament Rules can be found at <Wizards.com/WPN/Events/Rules.aspx>.