Sontaran-Prime

The  ordered that the Tenth Doctor was taken to the Sontaran war room. Once the Doctor and his companions were there, the Sontaran-Prime explained that the Sontarans had lost not only their clone worlds, but their battle forges, mega-systems and throne planets. Sontar stood still, but was on the brink of destruction, due to the Cybermen.

During an unexpected invasion, he sacrificed himself to protect the Doctor from a Cyberman coming out from a portal. (COMIC: Supremacy of the Cybermen)