Crafting Crag

Crafting Crag enters the battlefield tapped.
{t}: Add {r} or {g} to your mana pool.
{3}{r}{g}: Until end of turn, Crafting Crag becomes a 4/4 red and green elemental creature with "When Crafting Crag attacks, create a 0/4 red and green Elemental creature token." It's still a land.