Energy from Null

Energize (You may cast this spell by paying {e}
equal to its mana value; Instead of paying its mana
cost. If that spell has an X in its cost than you
may pay any amount of {e} for X.)
As an additional cost to cast this spell pay any
amount of {e}.
Exile X cards from each opponents library. Then
deal X damage times three divided among any
number of targets.Where X is the amount of
energy spent to cast this spell.