(: Add or to your mana pool.)
When Vault Oasis enters the battlefield, you lose 1 life unless you reveal a colorless card from your hand.
, , Sacrifice Vault Oasis: Put a -1/-1 counter on target creature.
, : Put a +1/+1 counter on target creature.
: Add 
or 
to your mana pool.), , Sacrifice Vault Oasis: Put a -1/-1 counter on target creature.
, : Put a +1/+1 counter on target creature.
