"The Barrier Mechanism"

The freezing process was so fast, yet people couldn't even see the ice layer on the victims' bodies! 

Actually, the ones freezing were the victim's inner organs and not the outer body. 

The moment the victim's heart got frozen, they would lose their life. 

At first, no one noticed anything, but when many people felt sleepy at the same time and some even suddenly 'fainted' with purple lips and pale faces...

The leaders realized something was wrong. 

"What happens? How come so many people fainted now?" 

Ainsley got the report from Scob and his people that some members of her guild had fainted with purple lips and pale faces. 

It seemed as if they were sleeping peacefully, but Ainsley got bad omens here. 

Indeed. The stronger members only fainted before they slowly lost their lives but weaker members would all die within minutes.