Zasshu Henshin Yajū is a Mon-Thro (or an anthropomorphic Monster ) a hybrid of 100 vertebrate earth animals 20 for each of his five forms.
younger forms have an average height of : 5ft or 152 cm adult forms have an average hight of : 6m or 600 cm
all zasshu forms can not speak exept for the avian forms
Zasshu H. Yajū, Zasshu, Henshin. Yaju he was made by the Doctor when the Doctor was a living alien life form, now the Doctor is a machine clone of the Doctors mind.
Zasshu, the mon-thro is made up of weird alien lifeforms indigenous to a planet called earth.
these earth animals that make up Zasshu are only part of the vertebrate animal groups consisting of 20 known and unknown earth animal DNA for each of Zasshu's 5 forms each of the 5 forms of Zasshu has a hybrid unique animal mix that is only "Visible" when Zasshu Transforms. Zasshu Mammal Form (Wolf/dog, Tiger/Cat, Panda, Deer, etc...) Zasshu Avian Form (Eagle/Hock, Humming Bird, Parrot, etc...) Amphibian Form (Salamander, Newt, Frog/Toad, etc...) Zasshu Reptile Form (Horned Lizard, Spitting Cobra/Cobra, Crocodile. etc...) Zasshu Shark/Marine mammal Form (Sward Fish, Orca Tiger Shark etc...) The doctor also included some Planarian for their strong/quick regeneration ability.
each of Zasshus forms has consistent parts from the other animals that are within his DNA like every one of Zasshu's forms has Scales/Fur wings, small to large hood, Extendable Fangs, large to small Gills etc...
even tho over half of the animal's DNA collected for Zasshu are, on earth proprietors, Zasshu and other Mon-thros feed mostly on fruit & unintelligent insects on the alien planet called Manna Sea.