The various Source Energies, when used and viewed from the eyes of those capable of seeing them, appear to converge on the the user at four different points. Lifeforms, such as the Ten-Tails is composed completely of Natural Energy. It is theorized that other lifeforms could be composed completely of other source energies. Ketsukiakushi is rumored to be composed completely of Lifeblood Energy, though its never confirmed nor denied.