The Thousand Demon Den. A cultivator's cave estate.

Shen Yi waved a hand slightly, and the jade slip before him flew into his palm.

He examined the two jade slips, then fitted them together — and found them a seamless match, as though formed that way by nature.

To draw Wutong Mountain's disciples in, he'd certainly had to pay something for it.

Shen Yi had noticed early on the jade slip Tong Xinchuan kept clutched in his palm, flickering unsteadily, as though guiding him in some direction.

Which was precisely why he'd cast out the Dark-Tail Spear at the end — to borrow this jade slip from the man.

So what treasure, exactly, could make them ignore so obvious a trap and come racing a thousand li to reach it?

Shen Yi closed his eyes and sank his spiritual sense into the jade slip.

【Return-to-Void · Soul-Forging Heavenly Thread: Not Yet Begun】

As he finished digesting the jade slip's contents, the panel likewise responded.

In the past, Shen Yi would certainly have had to pour in lifespan and study it thoroughly with the demons before he could understand what it was.

But now, a single glance was enough to set his heart leaping.

"Is this a formation?"

"No."

Shen Yi shook his head. Rather than a formation, it would be more apt to call this a means of laying formations.

Forge the spirit-soul, draw it out into threads, and then use those soul-threads to commune with the spiritual roots — thereby mobilizing heaven-and-earth qi in the most exquisitely fine manner possible.

If used for spell-combat it would certainly be of no use at all.

The thing was this meticulous precisely so that no error would arise in the laying of formations.

Like that formation Shen Yi had first encountered in a cave estate, which required Dragon-Flame Jade Fungus as its formation-material in order to condense waves of fire.

But with this technique in hand, any formation-material whose attributes matched one's spiritual roots could simply be replaced outright by the Soul-Forging Heavenly Thread.

Besides the basic soul-forging thread-drawing method—

the jade…