The Dinosaur Empire is a hidden civilization of evolved and sentient dinosaurs. After an influx of Getter Rays showered Earth, the remains of the original empire went into the magma of the planet in order to survive and one day retake the surface. They serve as the main antagonists of the original Getter Robo series and are the most recurring villainous group in the franchise as a whole.
Society and Structure
The Dinosaur Empire to ruled by a single monarchy with all known rulers being related to Emperor Gore. Its military is composed mainly of the Mechasaurus weapons that are piloted by soldiers with a ground army, an air force, and a navy. Each squads are commanded by captains and commanders of varying ranks. Many of the empire's soldiers do not fear death and in fact hold it as a pleasure.
In the series, the Dinosaur Empire rises from the surface to take it back from the humans who have evolved from the mammals that were on the surface with the Empire's absence. With all military weaponry little-to-useless against the Empire's military, the Getter Robo is called in to fight them. The robot was able to decimate their armies and destroy their forces at the end at the cost of one of their pilots.
However, in the manga timeline the empire still lingered and years later sent assassins before resurfacing after Professor Lando is dealt with to destroy their main enemy, the Getter Robo (specifically its current model Shin Getter Robo). But much like before, they are overpowered by the Getter Rays and are forced to retreat again.
With another time-skip, it is revealed that the Dinosaur Empire has entered an alliance with the Saotome Getter Ray Research Institute to fight the invading Andromeda Country and have developed a couple projects including using human DNA to make hybrids like Kamui Sho as well as the Gettersaurus. However, this was mainly used for the chance to destroy the Getter Robo as it is still the Empire's main threat. But after Kamui initiates a bloodless coup, he changes the plans to destroy humanity. What happens afterward is unknown.