The Skith Leader was a red coloured Skith who was in charge of a group of Skith the Dcotor encountered in 1915. When the Skith tried to invade in the artic. He came up with a plan to get hold of the doctors Tardis. He was defeated by the Doctor and thought dead. (DWM: The First)
But he did survive and had rebuilt Skith forces, he allied with Fanson a friend of Majenta Pryce. In 2010, he and the Skith planned to make a Skarids after the information they got from mind probing the doctor. However the Skith General betrayed him and pushed him down the Mindcore. He survived this attack but died once the Skith Genenral shot him. (DWM: The Age of Ice)