Megami Tensei series (Launched 1987) – Approx. 7.2 million units across 28 total editions (packaged and digital total)
Persona series (Launched 1996) – Approx. 8.5 million units across 13 total editions (packaged and digital total)
https://gematsu.com/2017/10/persona...on-megami-tensei-series-sales-top-7-2-million
Courtesy of Gematsu. Data for more series at the link.
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