The Darkness vanished.
Before the burning light of the Flame, the dark fog and its core vanished like morning mist into the gales billowing through the Desert of God. The root of its existence was utterly crushed by Joshua, with all nanometer-class runic constructs incinerated by searing fire into fundamental particles, returned to heaven and earth.
Clearness returned to world of Kronos. As that portion of Black Mist was utterly destroyed, the incessantly pouring black rain that was eroding the earth vanished. Though the mother-form of the Black Mist still existed at the other end of the Multiverse, this portion of it has dispersed, with the hundred-meters deep crater being the only trace of its existence. Clearly, if the few Legendary champions did not quickly work together to defeat it, the Black Mist could have simply dived beneath ground and erode the world bit by bit.