"Lord of Lords Ryu Knight: Adeu's Legend II" is a sequel to the original "Ryu Knight" series, continuing the adventures in the fantastical world of Zax. The story revolves around Adeu, a young knight who pilots the powerful mecha known as the Ryu Knight. Alongside his companions, Adeu embarks on a journey to protect Zax from the forces of darkness, particularly the malevolent Demon King and his minions. The narrative expands on the lore of the world, introducing new characters, factions, and challenges.

A central element of the plot is the struggle to gather the legendary Dragon Gems, powerful artifacts essential to defeating the Demon King. Adeu and his allies, including the spirited Princess Laine and the skilled warrior Elina, face numerous trials as they traverse diverse regions of Zax, encountering both allies and enemies. The series delves into themes of camaraderie, sacrifice, and the enduring battle between light and darkness, as the characters grow stronger and more determined in their quest.

The mecha battles are a significant aspect of the story, with the Ryu Knight and other mecha units engaging in dynamic and strategic combat. The series balances action with moments of character development, exploring the motivations and backstories of key figures. As the plot progresses, the stakes escalate, leading to a climactic confrontation with the Demon King and his forces. The resolution ties together the narrative threads, providing a satisfying conclusion to Adeu's journey while leaving room for the enduring legacy of the Ryu Knight.