Refined Phlogiston Development Materials An advanced material used for Weapon Ascension and Skill Upgrade for Pistols Resonators.

A crystal shaped like a solidified firework. After repeated purification, it is almost free of impurities. Its eye-catching and magnificent appearance not only holds practical utility but also elevates its collectible value.
Sources
Forgery Challenge: Abyss of Confession
Synthesis - Purification
Synthesis - Conversion
Forgery Challenge: Marigold Woods