Istantaneo — Trappola
Se esattamente una creatura sta attaccando, puoi pagare

invece di pagare il costo di mana della Trappola a Fossa.
Distruggi una creatura attaccante senza volare bersaglio.
Casting a Trap by paying its alternative cost doesn't change its mana cost or mana value. The only difference is the cost you actually pay.
You may ignore a Trap's alternative cost condition and simply cast it for its normal mana cost. This is true even if its alternative cost condition has been met.
Effects that increase or reduce the cost to cast a Trap will apply to whichever cost you chose to pay.