A discussion on the only known set of 84 mahasiddhas (normally shown in a single painting) where they are presented in individual portraits. The paintings were commissioned by Gyurme Tethong,the governor-general of eastern Tibet in 1920s, and are now in his grandson's possession in California. The author groups mahasiddhas into twelve categories, such as luminaries, scholars, those with physical ailments, and explains how they came to attain `siddhi'.