Underground Oasis enters the battlefield tapped unless you reveal a Specter card from your hand.
: Add to your mana pool. If you played a land this turn, Add to your mana pool instead.
, Sacrifice Underground Oasis: Add to your mana pool.
: Add 
to your mana pool. If you played a land this turn, Add 
to your mana pool instead., Sacrifice Underground Oasis: Add 
to your mana pool.
