Witch-Maw Disciple

{w/u}{t}: Tap target creature, it doesn't untap during it's next untap step.
{u/b}{t}: Target opponent puts the top card of his or her library into his or her graveyard.
{g/w}{t}: Create a 1/1 green Saproling creature token.
{w/b}{t}: You gain 1 life, target opponent loses 1 life.
{b/g}{t}: Exile target card in a graveyard.
{g/u}{t}: Put a +1/+1 counter on target creature.
{p/w}{p/u}{p/b}{p/g}: Untap Witch-Maw Disciple.