(: Add or to your mana pool.)
When Hollow Shelter enters the battlefield, sacrifice it unless you pay 1 life.
: Hollow Shelter becomes a 2/1 black and blue Rat Rogue creature until end of turn. It's still a land.
: Add 
or 
to your mana pool.): Hollow Shelter becomes a 2/1 black and blue Rat Rogue creature until end of turn. It's still a land.
