Swoosh!
A translucent, sparkling reddish barrier stretched taunt in front of Rex and Linthia, resembling thin, veined flesh pulsating faintly with life—its surface glistening as if alive, shifting and rippling with eerie, sinewy elasticity.
It was the filter barrier created through the Soul and Spirit Conversion method.
Normally, a person could literally cross to the Spirit Realm.
That person would remain exactly the same as in the mortal realm—retaining their full power.
But the problem with that method was that the Spirit Realm, much like the world's energy in the mortal realm recognized the invasion and would expel them—causing a heavy pressure on the soul. Unlike the world's energy that destroys the flesh, the world's energy in the Spirit Realm destroys the soul.
Due to that, only those with a strong soul could last long in the Spirit Realm.