Si costa meno, è semplicemente un costo alternativo.
Prowl
{B} (You may cast this for its prowl cost if you dealt combat damage to a player this turn with a Goblin or Rogue.)
Predatore
{B} (Puoi giocare questa magia pagando il suo costo di predatore se hai inflitto danno da combattimento a un giocatore con un Farabutto o un Goblin in questo turno.)
Cita:
702.73 - Prowl
* 702.73a - 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 Rule 601.2b and Rule 601.2e through Rule 601.2g. [CompRules 2009/07/08]
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,giusto?