Purifying Meditation

Tap target creature. It doesn't untap during its
controller's next untap step.
Purity {w} - Creatures you control get +1/+1
until end of turn.
Purity {u} - Draw a card.
(When this card is cast, if its cost was paid using
mana of only one color, activate the Purity effect of
the color of mana spent.)