The formation pattern that encircled Yan City vanished with Yan Ye's departure. Fortunately, Yan City had already completed its mission on the Central Continent. Ten thousand years ago, the Devil Emperor tore through the plane, leaving the Chaos Divine Source, the Absolute Kill technique, and the bracelet—items belonging to the Demon Queen—on Central Continent. It was, on one hand, to gather the Devil Queen's soul, and on the other, to await the return of the Demon Queen in this lower plane.
It was because each one of these items was of great importance that Yan Ye sent the left envoy of the Yanmo Heavenly Clan to guard them personally on Central Continent.
With the left envoy present, Yan City was established, and Yan Ye personally set up the formation pattern that isolated it from the outside world.