Roaring Spring

Enchant Land
Enchanted land has "{t}: Add {g} or {u} to your mana pool."
Naturecall - {3}{g}{u}, {t}: Put two +1/+1 counters on enchanted land and it becomes a 0/0 Elemental creature with haste. It's still a land. Activate this ability only if you cast a creature spell this turn.