Jiang Tang didn't eradicate all those Yin spirits; the first thing to do now is to kill the ancestor of the Invincible Sect, freeing these souls from his control, which is actually helping them!
He has already destroyed the Yin Soul Formation, and taking care of that Invincible Sect ancestor would be a piece of cake!
This ancestor of the Invincible Sect used such insidious means, he needs to be taught more of a lesson; letting him die so easily would be too lenient!
Jiang Tang personally doesn't have a grudge against such demons, nor is he a law enforcer of this time and space, but whenever he does something, there are always some rewards, so he doesn't feel any loss by doing so!
The traveler's actions are just convenient; whether it's upholding justice or suppressing evildoers, now that she has this ability, she needs to lend a hand, especially since the opponent's skill is so high that ordinary cultivators banding together wouldn't be a match!
