When a Mystic Human fuses with a Pranic Beast, they obtain the capability to transform into said Pranic Beast. They will retain every physical characteristic the respective Pranic Beast had.
They would only be unable to use the Pranic Beast's Natures. However, it didn't matter to them much, since they could crank psychokinesis through their bodies and drastically raise their combat prowess.
That wasn't all. Since a Mystic Human could treat their body as a Spirit Weapon, they generally severed their body parts–after assuming a Pranic Beast transformation–and wielded them as specialised Spirit Weapons.
Typically, Mystic Humans developed this ability to aid in the creation of puppets.
Mystic Nature Art–Spirit Puppet Slip!
Spirit Puppets had a Prana capacity of 100 units, but retained most of the physical might of the original. They couldn't freely transform. However, after the Mystic Human transforms into a Pranic Beast, he could create Puppets of the Pranic Beast form.
