Unseen Prairie

Unseen Prairie enters the battlefield tapped.
({t}: Add {g} or {w})
{2}{g/w}, {t}: Until end of turn, target creature you
contol gets +1/+0 and trample if it's green
and +0/+1 and vigilance if it's white.
Those who live on the grassland beneath the forest
canopy make clothes from the earth and weapons from
the trees.