Metamorphic Might

Target creature you control has base power and toughness X until end of turn.
Overload {x}{x}{w} (You may cast this spell for its overload cost. If you do, change its text by replacing all instances of "target" with "each.")
Convoke (Your creatures can help cast this spell.
Each creature you tap while casting this spell pays for
{1} or one mana of that creature's color.)
"Even a child can break a twig. But not even a giant can break a bundle."