Naraku's cave

is a new place...

History
As Byakuya retreat to the cave, he saw something darker that Naraku defile the Shikon no Tama to eliminate the light of Midoriko, in which Magatsuhi have been unleashed.

TBA

As the Shikon Jewel has been whole and been defiled, Naraku had become full power to unleash the miasma.