Historical Rules · 1 October 2009
Rule 112.6j
Official source text from the 1 October 2009 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 <http://www.wizards.com/Magic/TCG/Events.aspx?x=dci/doccenter/home>.