Historical Rules · 1 June 2014
Rule 100.6
Official source text from the 1 June 2014 Rules release
Most Magic tournaments (organized play activities where players compete against other players to win prizes) have additional rules covered in the Magic: The Gathering Tournament Rules (found at Wizards.com/WPN/Events/Rules.aspx). These rules may limit the use of some cards, including barring all cards from some older sets.