Under the explanation of Old White Wu Fengxian and Old Black Jiang Yuntian.
While they were alive, they had never heard of the Ancient City of Heavenly Origin, which means this ancient city came into existence after the deaths of Old White and Old Black.
As for wanting to leave here now, the only way is to break the barrier enveloping the ancient city. Now that the remnant soul power of Old White and Old Black has recovered considerably, they can lend Ye Chenfeng enormous energy.
However, to break the barrier, one must have the strength of a seventh-level Heavenly God Realm. In Ye Chenfeng's current state, even if Old White and Old Black could grant him the power of a seventh-level Heavenly God Realm in a short time, Ye Chenfeng's heart wouldn't be able to bear it and would burst from the pressure of their power.
In other words, it's impossible to rely on Old White and Old Black's power to break the barrier here.
After leaving the vast square.
