(Unstable Sandbar isn't a spell.)
Unstable Sandbar enters the battlefield tapped.
Creatures enters the battlefield tapped.
: Add or to your mana pool.
: Add to your mana pool. Put Unstable Sandbar on top of your library.
: Add 
or 
to your mana pool.: Add 
to your mana pool. Put Unstable Sandbar on top of your library.
