Scrub Caldera enters the battlefield tapped unless you sacrifice a creature.
: Add or to your mana pool.
Put Scrub Caldera on top of your library: Add to your mana pool.
: Return Scrub Caldera to its owner's hand.
: Add 
or 
to your mana pool.
to your mana pool. : Return Scrub Caldera to its owner's hand.
