Jungle of Lost Riddles

Unless you exile three cards from your graveyard, Jungle of Lost Riddles enters the battlefield tapped.
Discard a card, put the top two cards of your library into your graveyard, or exile three cards from your graveyard, {t}: Add {u}{b}, {b}{g},
{u}{g}, {u}{u}, {b}{b}, or {g}{g} to your mana pool.
Ancient buildings aren't just the only things that fall apart here.