This papercraft is Digitamamon, a Perfect Digimon that is mostly in an eggshell except for his dinosaur-like legs and golden eyes, from the anime, manga and video games series Digimon, the paper model was created by Hellsword.
Digitamamon can withdraw into his egg for protection and appears to have a near infinite space within his shell. He can control nightmare energy and release it from his eggshell. His name comes from "tamago", the Japanese word for egg, as a "Digi-Egg" called a "Digitama" from Japanese.
This paper model comes in three different versions: a normal Digitamamon, a Digitamamon which uses it's Nightmare Syndrome Attack and a Digitamamon which uses it's Enigma Attack.
You can download the templates here: Digimon - Digitamamon Free Papercraft Download