(: Add or to your mana pool.)
Foundry Karst enters the battlefield tapped.
: Foundry Karst becomes a 2/1 red and green Beast creature until end of turn. It's still a land.
: Add 
or 
to your mana pool.): Foundry Karst becomes a 2/1 red and green Beast creature until end of turn. It's still a land.
