If a card has an X in the mana cost, can I choose the color of X?
For example if I cast a fireball can I use green mana for X and have fireball become a Green/Red spell?
If a card has an X in the mana cost, can I choose the color of X?
For example if I cast a fireball can I use green mana for X and have fireball become a Green/Red spell?
No, Fireball is always a red spell regardless of what mana you spend to play it. After all, if you spend white mana on the colourless part of Runeclaw Bear, that doesn't suddenly make it a green/white creature, does it?
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