Diamond Ryugu is the primary antagonist of the series. She created pivotal Dragozaur entities such as Drago Wing, Gigano Dragon, and the Drago Clones. Leading the Dragozaurs, she commands minions like Dark Dragon and the Dragozaur Army Forces to achieve her goals, typically delegating tasks rather than fighting directly.

Her physical manifestation involves two interconnected forms. Initially, only her eyes and an effeminate voice are detectable. During battle, she fully reveals herself as a massive Ankylosaurus capable of breathing blue fire. A humanoid warrior form then emerges from the dinosaur's back, creating a centaur-like structure. This warrior form serves as her primary mode of interaction in confrontations.

Diamond Ryugu's core motivation is consuming lifeforce energy. She devours planetary lifeforce to sustain her power and pursue universal domination, making this consumption central to her role as a cosmic threat.

Information regarding her origin or evolution across different media remains unspecified. The character consistently functions as the overarching villain without documented development, alternate portrayals in spin-offs, or expanded backstory in OVAs or films. Her narrative centers on orchestrating conflicts through subordinates while pursuing energy absorption.