You don't have to spend all of the mana on the same cost.
2022-10-07
wotc
You can spend mana generated by the granted ability on any part of a cost that contains {X}. You're not limited to spending it only on the {X} part.
2022-10-07
wotc
You can spend mana generated by the granted ability on a cost that includes {X} even if you've chosen an X of 0, or if the card specifies that you can spend only colored mana on X. (You'll have to spend the {C}{C} on a different part of that cost, of course.)
2022-10-07
wotc
A "cost that contains {X}" may be a spell's total cost, an activated ability's cost, a cost to perform a special action, or a cost you're asked to pay as part of the resolution of a spell or ability (such as Condescend). A spell's total cost includes either its mana cost (printed in the upper right corner) or its alternative cost (such as flashback), as well as any additional costs (such as kicker). If it's something you can spend mana on, it's a cost. If that cost includes the {X} symbol in it, you can spend mana generated by the granted ability on that cost.
Format Legality
Standard
Not Legal
Future
Not Legal
Historic
Not Legal
Timeless
Not Legal
Gladiator
Not Legal
Pioneer
Not Legal
Modern
Not Legal
Legacy
Legal
Pauper
Not Legal
Vintage
Legal
Penny
Not Legal
Commander
Legal
Oathbreaker
Legal
Standardbrawl
Not Legal
Brawl
Not Legal
Alchemy
Not Legal
Paupercommander
Not Legal
Duel
Legal
Oldschool
Not Legal
Premodern
Not Legal
Predh
Not Legal
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