Perilous Precipice

({t}: Add {r} or {g} to your mana pool.)
Perilous Precipice enters the battlefield tapped.
When Perilous Precipice enters the battlefield, reveal the top card of your library. If
it's a land card, untap Perilous Precipice.
"It's unsafe ground there, but worth the risk to see the inside of the temple at the top."