(: Add or to your mana pool.)
Grass-Flats enters the battlefield tapped.
: Grass-Flats becomes a 2/1 green and black Elf creature until end of turn. It's still a land.
: Add 
or 
to your mana pool.): Grass-Flats becomes a 2/1 green and black Elf creature until end of turn. It's still a land.
