Orochimaru's energy clone was also a Ninjutsu developed based on his own physical constitution.
Chakra is likewise a form of energy, and Tailed Beasts are entirely composed of chakra energy; Orochimaru's energy clone, however, was formed by condensing physical energy.
Though incapable of using chakra or various ninjutsu, it could sustain itself by absorbing energy from the external environment.
Chapter 78