I'm Already at the Mahayana Stage, and the System Only Just Arrived

After transmigrating to the Kyushu Continent, Chen Fan starts out with no golden finger.

For three hundred years, he cultivates alone, overcoming one obstacle after another until he reaches the peak of the Great Ascension stage through sheer effort, just one step away from ascending to the Immortal Realm.

Just then, the late-arriving Comeback System finally activates, a full three hundred years later.

[Ding! Comeback System successfully bound!]

[Host cultivation detected: Qi Refining, First Level]

[Beginner comeback mission: Defeat the Wang family, who have been bullying the Chen family. Wang family head's cultivation: Foundation Establishment!]

Chen Fan: "...???"

Foundation Establishment?

He's a mighty Great Ascension expert, and now he's being told to take down someone at the Foundation Establishment stage?