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Historical Rules · 1 October 2010

Rule 205.4

Official source text from the 1 October 2010 Rules release

Players may include cards from any printing in their constructed decks if those cards appear in sets allowed in that format (or those cards are specifically allowed by the Magic Tournament Rules). See the Magic Tournament Rules for the current definitions of the constructed formats (http://www.wizards.com/Magic/TCG/Events.aspx?x=dci/doccenter/home).

Find this number in the current Rules