You need good research and references to create photorealistic creature. This is the collection of 13 photorealistic creature makings in maya, to give you idea about how to create Photorealistic Creature.

Making of Tiger Zoo

Sunbathing – American Alligator 3D Modeling

Making of Trapped

Making of Male Green Frog

Making of Chameleon

Making of the Prince

Making of Say Cheese by Vaibhav Shah

Making Of Sea Turtle by Katrin Schmid

Build an ELEPHANT

Making a Giraffe

Modeling a dragon

Godzilla WIP/Tutorial – Day 1 (Blocking in Maya)

Modeling of a tarantula

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