Markus is a named patient of asylum section of Castle Wolfenstein's Prison in Wolfenstein: The Old Blood. He knows of Helga's secrets and realizes she knows when William J. Blazkowicz enters the patient section of the castle. If B.J. interacts with him and ask of Helga's secret, he will think B.J. is his son and will rejoice. B.J. tells him he is not his son and will leave to continue with his mission.
|Organization||101st Airborne Division · United States Army · SS Paranormal Division · SS Special Projects Division · Office of Secret Actions|
|Resistance||BJ Blazkowicz · Annette Krause · Pippa Shepherd · Fergus Reid · Ludwig Kessler · Richard Wesley · Katrin · Markus · Village Drunkard|
|Nazis||Rudi Jäger · Helga Von Schabbs · Emmerich Schreiner ·|
|Other||Otto I · Eadgyth · Konrad · Siegbald Berger|