Rule 702.56a

Replicate is a keyword that represents two abilities. The first is a static ability that functions while the spell with replicate is on the stack. The second is a triggered ability that functions while the spell with replicate is on the stack. “Replicate [cost]” means “As an additional cost to cast this spell, you may pay [cost] any number of times” and “When you cast this spell, if a replicate cost was paid for it, copy it for each time its replicate cost was paid. If the spell has any targets, you may choose new targets for any of the copies.” Paying a spell’s replicate cost follows the rules for paying additional costs in rules 601.2b and 601.2f–h.