The group of cultivators were all shocked. The grand formation that was taking away their life force was something literally no one had ever heard of!
Taking away someone's life force was a technique of the Great Dao. Even a True Immortal Realm immortal might not necessarily be able to display that kind of technique. This Immortal Void Realm grand formation, however, could imitate the functions of that technique!
Within the grand formation under the lightning flashes and falling rain, the life force of all of the undead spirits regardless of whether they were allies or enemies were decreasing rapidly. Their hair turned white and their faces gradually aged.
A few experts whose lifespans were about to run out lost their final trace of life force and died after being affected by this grand formation.
It was only a matter of time before the other experts who were also trapped inside this formation lost their life force completely.