Malum Island

Malum Island enters the battlefield tapped
{t}: Add {u}, {b} or {g} to your mana pool
{u/b}{b/g}{g/u} {t}: You Explore (Reveal the top card of your library. Put that card in your hand if it's a land. Otherwise, put a +1/+1 counter on a creature you control, then put the card into your graveyard)