Fanged Marsh

{t}: Put the top card of your library into your graveyard. If it was a creature card, add {b/g} to your mana pool.
{3}{b}{g}, Exile a creature card from your graveyard: Until end of turn, Fanged Marsh becomes a 3/3 black and green Elemental creature token with deathtouch and reach. It's still a land.
"Why would you ever want to live in a place where the plants grow teeth?"