The "Great Nirvana Heart Sutra", the technique left by the ancestors of the Phoenix Race, was not the most powerful technique in the Realm of Heaven. But it was definitely the most suitable technique for people with Phoenix blood.
Ming Huang only had a thin Phoenix bloodline, but this was enough.
As long as he used the Great Nirvana Heart Sutra to constantly break through, the Phoenix bloodline would become more and more refined, and Ming Huang would become a true member of the Phoenix Race by then.
The people of the true Phoenix Race had powerful combat power.
If they could reach the height of the ancestor of the Phoenix Race, they could dominate one side in the Realm of Heaven and become an existence above thousands of immortals and demons.
Mo Xiu's goal for Ming Huang was to reach the height of the ancestor of the Phoenix Race.