So a friend of mine bought a new deck today which is (heavily) based on Extort ability:
Whenever you cast a spell, you may pay If you do, each opponent loses 1 life and you gain that much life.
So now I wonder how exactly does it work? Does he have to pay for EACH creature with Extort for each spell he plays or is 1 enough to let Extort trigger from all creatures? An example:
A player has 5 lands and 3 creatures with Extort ability. He then plays an Oblivion Ring for 3 mana(), so he now has 2 mana left. If he taps one, would all 3 Extorts trigger or just one?
From the text I would assume the following:
Whenever you cast a spell, if you pay extra, then Extort ability will trigger.
So am I right or is Extort a pretty useless ability that should be paid on each creature separately?