Probably the Pater of the Mithraeum of Ostia which bears his name.
Biography of Felicissimus
Felicissimus is known for the mosaic in his temple which represents the Mithraic ladder with the seven grades and its attributes.
Other brothers from Ostia
The Felicissimo Mithraeum has a floor mosaic depicting the seven mithraic grades.
FELICISSIMVS / EX VOTO F[ecit]
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