Spiteful Will

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
When this spell resolves, target player loses 2 life.
Splice onto Curse - {b}, Pay 1 life. (As you cast a Curse spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)