It's sad that the manhua completely left out the explanation for MFZ's motivation for going after the members of Orchid Monarch Hollow Bamboo.
To sum it up as short and concisely as possible, he left behind messes in the pugilistic world during his time he was active. Part of his goals now is to clean up the mess. You have to read the novel to understand the entire arc.
I'm bummed that the fight was nowhere near as intense as it was in the novel. Oh well.
In a sense, the two parallels of the story are the present and the past which is to be revealed in a similar fashion to peeling an onion.