原文The last triggered ability targets the opponent. If that player is an illegal target as the ability tries to resolve, the ability won't resolve and none of its effects will happen. You won't exile a card.
原文You choose whether or not to cast the instant or sorcery card as the last triggered ability resolves. If you do, you do so as part of the resolution of that ability. You can't wait to cast it later in the turn. Timing restrictions based on the card's type are ignored.
原文If you cast a card "without paying its mana cost," you can't pay any alternative costs. You can, however, pay additional costs. If the card has any mandatory additional costs, those must be paid to cast the card.