Mammoth Bellow (#205)

Type: Sorcery

Text: Create a 5/5 green Elephant creature token.
Harmonize {5}{G}{U}{R} (You may cast this card from your graveyard for its harmonize cost. You may tap a creature you control to reduce that cost by {X}, where X is its power. Then exile this spell.)

Set: Tarkir: Dragonstorm (#205)