Ancient Cavern

Ancient Cavern enters the battlefield taped.
As Ancient Cavern enters the battlefield, choose
a creature type.
{t}: Add 2 to your mana pool.
{t}: Add two mana of any color to your mana
pool. Spend this mana only to cast a creature
spell of the chosen type, and that spell can't be countered.
Creatures of the chosen type get a +1/+1