Factor, the Critical Aspect

Whenever you cast a spell with {x}in its mana cost
or activate an ability with {x}in its activation cost,
if X is greater than 0, draw a card for each {x}in
that cost.

{u/r}{u/r}, Exile your hand: Change the value of {x}of target spell or ability to the greatest mana value
among cards exiled this way. Activate only if you
have two or more cards in hand.