Bab 175: Chapter 175: <Spoiler>

"That… that is… Impossible! Philosopher's Stone!?" Envy exclaimed in awe. The word 'shocked' was an understatement as she beheld Daniel's revelation. Unlike Greed, who knew that creating a Philosopher's Stone out of thin air was impossible, Envy understood the reasons behind its impossibility—a knowledge often forbidden to most mages.

The reason it was deemed impossible was rooted in the fact that the ritual to create a Philosopher's Stone required the soul of a victim as a sacrificial component. Half of the success of the ritual hinged on a contract with Mephistopheles, a deal to bless their ritual for absolute success, in exchange for half of the souls used to create the Philosopher's Stone.