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