Ethan has two options in front of him. One, kill the Berserk Beasts, and two, cure them.
Killing them might give fewer Life Points; however, it is quick and easy, whereas curing them gives 10 times more Life Points, but it is a time-consuming process of at least 3 minutes for a Rank 1 Berserk Beast, not to mention the higher the grade of the Berserk Beast, the longer it will take.
But, as an emotional person from the modern world, Ethan cared for all living beings, and after learning that he had the ability to cure them, he didn't want to kill them.
Just as Ethan was thinking that turning the Berserk Beasts into Spirit Beasts was taking too much time and Spirit Essence, he suddenly thought of something that made his eyes light up.
'Why don't I use the Infernal Flame in my heart to burn away the Demonic Blood Dragon's Essence?'
Ethan believed that it would be quick and easy to turn the Berserk Beasts into normal Spirit Beasts.