It turned out that they made a trade by allowing Gold to acquire Gideon's heart, and since Gold is still the Dark One, Emma is still the Savior, which means the final battle will happen.
It turned out that they made a trade by allowing Gold to acquire Gideon's heart, as Gold is still the Dark One as he wanted to retain his powers. This means that Emma is still the Savior, and the final battle will happen.