As for Decay, it was a death elemental technique that corrodes a living organism's cell. Essentially, a single targeted skill could make a living organism enter a state of decomposition while alive. Unlike the Death Ozone, which was AOE. Because of this, the effect of Decay was far more effective.
Fein already tried it on plants and animals. The result was, all of them rot at an incredible speed. Of course, it would be far less effective against stronger creatures. Fein could only use the Decay on enemies that were only one realm higher than him. For instance, if he uses his Decay to an SS rank realm, the SS rank realm's flesh won't decompose because of the strong resistance of his SS rank degu energy. Though, it would still slow down his regeneration speed and get affected by a series of debuffs such as stiff movement, dizziness, and fast consumption of stamina.
