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As Gustav underwent a "training" of sorts outside, he was still living another life inside of his divine realm. In there, he was using his second body to mostly maintain the entire place, using his powers and divine energy to nourish the land and the farms, while keeping everything on check of not losing its balance.
After he became a Supreme God, his entire divine realm exploded with many new divine materials, which were all sorts of materials of magical properties that appeared out of thin air through the materialization of over accumulation of divine energy and elemental attribute particles.
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