Johann George Schrepfer’s life story is clouded by his embellished and falsified tales of his necromancy and spiritualism. And both his followers and detractors also gave biased and incorrect accounts of their interactions with him.
Research:

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Britannica, The Editors of Encyclopaedia. "necromancy". Encyclopedia Britannica, 2 May. 2011, https://www.britannica.com/topic/necromancy
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Museum - Naturalienkabinett Waldenburg. "Laterna magica" last modified 2021-11-26. https://global.museum-digital.org/object/1876368
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