This is not mere luck.
Those who failed before mostly tried to externalize the power of their Inner Array Realm, forming a Law Domain to suppress the Great Void. But because of this, their Law Domains simultaneously contacted multiple Heavenly Sea areas with differing Time Flows, where some places were fast, some were slow, and their own power tore them apart.
However, Yu Feng transformed the Law Domain into an ark of adaptable size—every time he entered an area with a different Time Flow, he would reduce it to exist only in that region. In this way, he wouldn't need to simultaneously control the domain to accelerate or decelerate in over ten different areas, just one place at a time.
Though it was a trick, it proved Yu Feng's control and observational skills regarding his Law Domain.
"Still revealed a bit of my hand."