Most of the stalls were filled with miscellaneous items, none of which were of value to Xu Hei, as he was merely an ordinary late-stage Great Ascension cultivator.

However, there was one item that caught Xu Hei's particular attention.

It was a mass of black, viscous substance, stored in a large vat, resembling either sludge or fine quicksand.

As soon as Divine Sense was used to probe it, it would silently disappear.