"Last Survival" 

The experiment with the light-coated bullets worked well, and the experiment with the holy water also gave satisfying results. 

"We need ten drops of holy water to kill a seriously injured low-level demon and exactly one thumb-sized bottle of holy water to kill a seriously injured mid-level demon." 

A thumb-sized bottle might contain a hundred drops of holy water, which showed the gap between a low-level demon and a mid-level demon. 

Still, this method worked well as long as there was someone manipulating the water to hit the target. 

Then, there were also talismans made by array masters who joined hands with priests because they had to make a purifying talisman. 

The group tested the talisman, and one low-level demon could be killed entirely without being heavily injured just by pasting one talisman to the heart of the demon!