Spell Blast

Alternative costs, additional costs, cost increases, and cost reductions don't affect a spell's mana value.

If the target spell has X generic mana in its mana cost, include the value chosen for that X when determining the value of the X generic mana in Spell Blast's mana cost. For example, if you wish to counter Volcanic Geyser (a spell with mana cost X generic mana red mana red mana ) whose X is 7, you'll need to choose 9 for Spell Blast's X and pay 9 generic mana blue mana .