The reason why Li Fan could easily suppress the Grand Master this time was because of the Soul-Stripping Blade, which inherently restrained him. The Grand Master's Limitless Dao was truly vulnerable before the [True Yet False].
However, when facing the Hungry Immortal, the [True Yet False] wouldn't be as effective.
Before Spirituality was reduced to its lowest point, the Hungry Immortal's half-step Nameless strength was enough to grind the original Fairy Puppet into ashes. After all, without Hai Zhen to provide a fallback, Li Fan would not easily step in when eliminating hidden threats around the Xuan Huang.
As for the Phantom of the Guarded Hill...