Muren

 was a Time Lord commander in charge of the mission to rescue Ollistra and didn't feel comfortable about handing over the plans of his mission to the War Doctor. He helped the Doctor on Rovidia. After the Sontarans came after them, he thought that the local Kalan had betrayed them. He had an executive order to execute Ollistra to stop her falling into the hands of the enemy. He was shot by a Sontaran and died. (AUDIO: The Eternity Cage)