(Ravaged Barrens isn't a spell.)
Ravaged Barrens enters the battlefield tapped.
, : Scry 2.
: Add or to your mana pool.
Put Ravaged Barrens on top of your library: Add to your mana pool.
, 
: Scry 2.: Add 
or 
to your mana pool. to your mana pool. 
