The Mighty Meek

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.)
Strive — This spell costs {2}{g/w} more to cast for
each target beyond the first.
Any number of target creatures get +X/+X until
end of turn, where X is the number of creatures
you control.