When a reincarnation of the Strongest Mortal Soul dies a part of the original soul forms his personality in the soul realm. This is a realm made by the original incarnation as a way to gather his future reincarnations to train for the inevitable final battle.
Among those many reincarnations, there were swordsmen, archers, barehanded fighters, and many more, and among those groups, the mages were the ones who talked to each other the most.
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"Of course, the best form of a magician is being an alchemist. It combines the greatness of science and the miracles of magic. We can create potions that can even resurrect the recently deceased, and we can even create elixirs that can alter reality or enhance abilities to a ludicrous degree."
Hanz Heiter was the reincarnation who represented the alchemists as he was considered to be the very first alchemist the one who started the school of alchemy.
