Kreos

Kreos is the leader of the Thal Military when the First Doctor, Susan, Ian and Barbara returned to Skaro more than 50 cycles after the Thals defeated the Daleks in their city. (AUDIO: Return to Skaro)

Biography
When the Doctor, Susan, Barbara and Ian arrive at one of the ionizing towers on Skaro, two armed Thal guards, Adoni and Gerasus, exit the tower and order them to stay where they are and that they are in a restricted zone. Kreos approaches telling Adoni to stand down and lower there guns, he apologises for Adoni's enthusiasum and asks them who they are, when the Doctor introduces himself, Kreos realises that this is the same Doctor and his companions that helped libarate Skaro and the Thals from the Daleks. Susan asks Kreos how Alydon and Dyoni are, but Kreos tells her that the time of Alydon and Dyoni has passed, however their descendant Damadus now leads the Thal people and offers to take them to him.

The Doctor asks Kreos what these towers are, as they were not on Skaro when they first arrived, Kreos takes them inside the tower and explains that this tower is the control station for the tower network in this region and that Adoni and her team can control more than 30 towers from this location. Kreos explains that these towers where created to reduce the level of background radiation left over from the neutronic war, by using the electrical discharges generated from the towers to ionize the atmosphere, reducing the half-life of radioactive particles in the atmosphere by a factor of 10, to which the Doctor agrees as neutron radiation is an ionizing radiation.

Kreos tells them that there are towers all across Skaro, although not all of them are complete and that the operation only started 2 years ago by the Thal's foremost scientist, Tryana. (AUDIO: Return to Skaro) Susan asks how the electricity is generated so Kreos orders Adoni to prepare an ionizing shot for a demonstration, he explains that they feed static electricity into a dynamo above them and when it is suitable energised, it is discharged into the tower and the electrical charge arcs to the nearest tower, Ionizing airbourne particles on the way, however they cannot aim the discharges. He says that the towers are made from an alloy of a extreamly strong metal ore which the Thals call "Skaronium" and that there are nano-particles in every static electrical discharge that target the atomic structure of that alloy.

Ian realises Kreos said static electricity, knowing that's what the Daleks used as a power source and asks if the towers are Dalek technology, Kreos replies saying that the Thals have adapted to Dalek technology for their own purposes, Susan reminds Barbara when she said to Alydon that Dalek technology could be of use to the Thals, showing he took her advice. Kreos says that Thal scientists and architects made great use of the Daleks technology, exclaiming that the Thal City is the "jewel of Skaro". The Doctor replies saying it would be good to meet the descendents of Alydon and Dyoni and the scientist Tryana, however they have to walk to the city as their transports only work on metal surfaces, Kreos then orders Adoni to inform the city and Damadus that they will be with them shortly.