This is a good, brief summary of the life of Mani and his influence. It concludes with some theological reflections. I leave you to evaluate those yourself.
If you would like a much deeper dive into Mani's life, including the question of the date of his death, see Werner Sundermann's article MANI in the online Encyclopaedia Iranica
One thing Revd. Ford's essay does not mention is that one of Mani's scriptures was a version of the Book of Giants. It was perhaps written in Syriac and seems to be based on the Jewish Aramaic Book of Giants, fragments of which survive in the Dead Sea Scrolls. Our surviving fragments of Mani's Book of Giants are written in Middle Persian (various languages) and Old Turkic translations.
For some PaleoJudaica posts on the Book of Giants, see here and here and links.
The second volume of the More Old Testament Pseudepigrapha Project will include translations of all surviving fragments of the book.
For many posts on the prophet Mani, see here, here, here, and links.
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