In his childhood eighty five years ago, a noted event Xznaal remembered was visiting the plantations of Mare Sirenum where he became lost in the withered bushes. Once there, he discovered a winter berry and plucked it from its vine. Being both beautiful to see in its vivid orange form against the ash-brown branches, he took a bite from it. It was then he learnt that the inside of the fruit was black and putrified without leaving any external sign. Instead of spitting it out, he swallowed what he had bitten off and decided to never forget that moment of his life as it showed that his world was dying. When he reached adulthood, he stood side by side with his bitterest rivals of the clans of Thaumasia and Erythraeum. There they stood united in grief at the passing of Marshal Kyruul and stood in celebration of the crowning of the boy king Paxaphyr.
During the Mars Project in 1977 where a mission was sent from Earth to Mars for exploration, the human Lord Edward Greyhaven discovered Xznaal and the Martian civilisation. In order to capitalise on this event, Greyhaven decided to make events seem that the mission was a failure and kept the existence of the Ice Warriors a secret for twenty years. He expected to gain technical knowledge from Xznaal and enhance his own position. However, the ruler of the Argyre Clan had other plans.
In 1997, through his alliance with Lord Greyhaven, he managed to orchestrate events to allow for a "legal" invasion of the United Kingdom under Martian law. This was based on the events of British astronauts on Mars entering the Fields of the Dead and the tomb of Kyruul. With the events in place, he took his warship to London where he declared the United Kingdom a conquered territory of the Argyre clan. With the aid of Lord Greyhaven, Xznaal attempted to further legitimise his rule especially in the eyes of the Eighth Doctor. Claiming that Mars was dying and that they were facing extinction, he made it appear that it was a mutual alliance and that his people simply wished to co-exist with the human race.
After facing increased opposition to his rule, he unleashed the Red Death; a biological weapon that sought out its targets by their DNA which in this case was the Doctor. When his clan was destroyed by the Mars Orbiter, Xznaal went mad with grief and intended for the entirety of the human race to be wiped out by the Red Death plague. However, he was killed when the RAF destroyed his warship which was floating ten kilometres above London. (PROSE: The Dying Days)