502.76. Prowl

502.76a Prowl is a static ability that functions on the stack. "Prowl [cost]" means "You may pay [cost] rather than pay this spell's mana cost if a player was dealt combat damage this turn by a source that, at the time it dealt that damage, was under your control and had any of this spell's creature types." Paying a spell's prowl cost follows the rules for paying alternative costs in rules 409.1b and 409.1f-h.


409.1f The player determines the total cost of the spell or ability. Usually this is just the mana cost (for spells) or activation cost (for abilities). Some cards list additional or alternative costs in their text. Some effects may increase or reduce the cost to pay, or may provide other alternative costs. Costs may include paying mana, tapping permanents, sacrificing permanents, discarding cards, and so on. The total cost is the mana cost, activation cost, or alternative cost, plus all additional costs and cost increases, and minus all cost reductions. If the mana component of the total cost is reduced to nothing by cost reduction effects, it is considered to be . It can't be reduced to less than . Once the total cost is determined, it becomes "locked in." If effects would change the total cost after this time, they have no effect.