A Bunachu is a strange species of Pokemon that looks like a Buneary with a tail from Pikachu. This Pokemon is created when a male Pikachu mate with a female Buneary. Normally, a baby Pikachu or Buneary should be hatched from the egg. However, Bunachu is created when there is a genes mutation in the body of either a Pikachu or Buneary, which change the Pokemon entirely.
The whole body of Bunachu, except the tail, is made up of Buneary's body. The entire body is yellow - the same colour as Pikachu. It has a tail shaped as a Pikachu's one. It also have two red circle on its cheeks, similar to Pikachu's. Bunachu is a Normal and Electric types, and can use both its parent move.
Bunachu can learn all its parent move and some of its own unique attack. It can use an Electric-type move Thunder Ears. More strange, gross and unique moves are yet to be discovered.
There is only one Bunachu, bred by humans, not in the wild. Bunachu was discovered by some extremely idiotic guy and some hysterically crazy girl at December 2009 when Ash's Pikachu breed with Dawn's Buneary. The results is the egg hatched into a Bunachu.
Bunachu is formed when there is a gene mutation in either in Pikachu or Buneary body, resulting the substance in the genes read the genes incorrectly, which gave Bunachu a yellow body, a Pikachu's tail and a black fur on its ear. Investigations is still ongoing.
Not known for its behaviour because Ash's Pikachu and Dawn's Buneary stopped those annoying scientists an reporters from interviewing Bunachu (including Professer Tree). Some predict that Bunachu have a "want-to-kill-people" nature, because Bunachu may not handle the Electric-type moves.