Dyscalculiation Mage

Flash,
Dyscalculiation Mage enters the battlefield
with up to 3 +1/-1 counters on it.
When Dyscalculiation Mage enters the battlefield,
you may increase or decrease the value of target
spell with {x} in its casting cost equal to
Dyscalculiation Mage's power.
The risk I took was calculated...
But wow I'm bad at math