The Binding Technique, a Minor Divine Power of the Jinxian Sect.
This Dharma Technique might be one of the staple Minor Divine Powers of the Jinxian Sect, being something disciples can self-teach upon reaching the Sixth Stage. It may not seem as potent as those of other sects, but it's incredibly practical!
Cultivating isn't all about being strong in combat, that's just one aspect of it.
And right now, this Binding Technique is extremely useful!
The main issue is that advancing to the Sixth Stage was too rushed. Just after their breakthrough, these people arrived. If they had had more time, letting Zhang Fei Xuan cultivate Minor Divine Powers that would suit his own Dharma Techniques could have greatly improved the situation.
The moment Zhang Fei Xuan cast it, that person clearly stiffened in place, yet the stiffness wasn't apparent, as they began to move their head.