As Secluded Courtyard enters the battlefield, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature or creature card of the chosen type.
If Secluded Courtyard is somehow on the battlefield without a chosen type, mana from its second mana ability can't be spent on anything.