(Stadium Ravine isn't a spell.)
Stadium Ravine enters the battlefield tapped unless you sacrifice an enchantment.
, : Look at target player's hand.
: Add or to your mana pool.
Put Stadium Ravine on top of your library: Add to your mana pool.
, 
: Look at target player's hand.: Add 
or 
to your mana pool. to your mana pool. 
