Historical Rules · 1 October 2012
Rule 702.94a
Official source text from the 1 October 2012 Rules release
Overload is a keyword that represents two static abilities: one that functions from any zone in which the spell with overload can be cast and another that functions while the card is on the stack. Overload [cost] means "You may choose to pay [cost] rather than pay this spell's mana cost" and "If you chose to pay this spell's overload cost, change its text by replacing all instances of the word 'target' with the word 'each.'" Using the overload ability follows the rules for paying alternative costs in rules 601.2b and 601.2e-g.