Magog

Magog was the most fearsome and powerful of the Malevilus that were worshipped as gods by an alternate Rome. He took over the body of Adolphus Caesar's mother Juno, and planned to do the same to Adolphus when he succeeded the throne. the Doctor tricked Magog into being imprisoned in an empty dimension. (DWM: The Iron Legion)


 * In Divided Loyalties, Magog is named as one of the Great Old Ones. It is unclear if the two entities are one and the same.