Dr. Kroenen was a German scientist fascinated with the idea of extending life and conquering death and had been active since the 1920s. As he aligned with the Nazis and as a member of the Thule Society was believed to have been involved in the attempts to harness the "Shakti" energy force.
A devestating accident left Kronen severely injured. Desperate life-saving surgeries transformed him into a grotesque figure, resembling one of his own monstrous creations, forcing him to be permanenly encased in a protective bodysuit.
Devoting himself to serving Gregori Rasputin, Kroenen became a loyal follower and trusted enforcer. While his primary duty was to serve Rasputin, he was permitted to pursue projects aimed at creating an unstoppable army for the Reich.
Speculation abounds regarding Kroenen's potential success in his endeavors, including the possibility of his involvement in the outbreak of the zombie plague. Some believe that he manipulated the ZomPoc to advance his unhinged research. Unverified reports have emerged of undead creatures clad in uniforms akin to those worn by German troops during World War II.