(Flagstones Thicket isn't a spell.)
Flagstones Thicket enters the battlefield tapped unless you pay .
, : Look at target player's hand.
: Add or to your mana pool.
Sacrifice Flagstones Thicket: Add or to your mana pool.
.
, 
: Look at target player's hand.: Add 
or 
to your mana pool. or to your mana pool.
