Kempler held dual roles as Count Egobossler's commanding general within Galactor: Director of Strategic Intelligence and Captain of the Imperial Guard. As Egobossler's primary intelligence officer, he gathered critical information to advance Galactor's goals. Highly intelligent yet employing despicable, cowardly tactics, Kempler showed particular cruelty towards vulnerable targets like children. He harbored deep-seated ambitions for power, feigning loyalty to Egobossler while secretly plotting to overthrow him and seize control of Galactor. This drive stemmed from personal ambition and growing paranoia, fostering distrust within the organization. Kempler used the Rider Commandos to uncover the secret of Egobossler's birth, enabling his betrayal. He successfully trapped Egobossler, temporarily usurped his position, and launched an all-out assault against the Science Ninja Team's base and Dr. Nambu. During his coup, he collaborated with Egobossler's imprisoned half-brother, Kassel, intending to install him as a puppet leader. Kassel died in battle, leaving Kempler to pursue sole control over Galactor. His betrayal ultimately failed. After Dr. Nambu's death, Egobossler regained power, captured Kempler, and sentenced him to death for treason. Dismissing him as a coward, Egobossler ordered Kempler's execution by firing squad carried out by Galactor troops. Physically, Kempler was tall and muscular. He wore a distinctive lavender-blue military suit with red accents, a matching cap featuring golden ear covers that often obscured one eye, a black cape, gloves, and boots. His wild, dark brown hair and beard were slightly shorter than Mechandol's. Kempler's narrative arc concludes with his execution.