By the year 2371, Stentor was very old for a Sontaran. General Skelp believed him the oldest Sontaran he had ever met. Stentor wore armour from the Koda branch and a blue gold-trimmed sash. He also carried a battle standard rather than a Sontaran baton as befitted his rank. It doubled as a cane. His voice was raspy from age and possibly from multiple woundings. Skelp mentioned that the Fleet Marshal had not led a sheltered life, indicating he had fought in many campaigns. Stentor was vain. He wished to show his comrades at the Grand Strategic Council that his theories on winning the war were correct. Stentor suffered pain in his legs from his extreme age, but would not sit in a command couch whilst on the bridge, preferring to lean against his battle standard.
In 2371, Stentor commanded the task force integral to a long-planned operation to move into a sector of space of the dead Tzun Empire. The operation was a complicated manoeuvre to draw out a Rutan fleet protecting their base in the Antares system and then using nucleosynthesis on the gas giant Indra in the Unukalhai system to create a miniature star and destroy the heat-averse Rutans. The Sontaran task force would then move against the unprotected Rutan base in Antares to begin expanding onto the former Tzun worlds.
On arriving at the Sontaran fleet assigned to the Antares operation, Stentor disciplined the individual commanders to improve the disposition of the fleet. He nominally oversaw the final stages of the Sontaran plan in the Unukalhai system, eventually ordering progress sped up; Rutan probes were approaching.
When the Rutans jumped into Hyperspace, the Sontaran fleet fleet jumped to Antares. However, the Rutans had been informed of the Sontaran plan by the Doctor. They jumped back to Antares, surrounded the Sontaran fleet and attacked. Thus began the Battle of Antares.
For a while, Stentor's genius resurfaced. He held back the Rutan fleet and inflicted many casualties while receiving many in return. He was prepared to die fighting when a decrypted Rutan transmission changed his priorities. On learning of this intelligence, he was about to order the fleet to a defensive position which would allow at least some ships to escape with the Intel. It was then that one of the officers attached to his staff, Karne, revealed himself as a Rutan spy and killed the old Sontaran Fleet Marshal to disrupt the dissemination of the vital intelligence. (PROSE: Lords of the Storm)