Elven Druid's Cavern

{t}, Pay 1 life: Add {g}.
{5}{g}, Exile Elven Druid's Cavern from your
hand: Exile cards from the top of your library
until you exile a Creature with converted mana
cost five or less. You may cast that spell without
paying its mana cost and put the rest on the
bottom of your library in a random order.