The Sixth Tamasan was a Time Lord who worked for Cardinal Ollistra during the Last Great Time War.
After regenerating once more, Major Tamasan expressed a distrust towards Bliss to the Eighth Doctor over a call to his TARDIS. (AUDIO: State of Bliss)
When confronted by the Doctor that the War "must be going well" due to her constant regenerating, she responded that "it [was] always an honour" to serve Gallifrey in any way she could. (AUDIO: The Famished Lands) The Doctor later contacted her to ask that their armies steer clear of the Seas of Nemacene, having made a promise to protect the trade routes there and save planet like Iptheus from total starvation. Tamasan updated the Doctor on a recent victory over the Daleks, and refused to offer such a protection. After informing him of the Dalek Time Strategist's newest plans, which were threatening the multiverse, Tamasan was called away to the Panopticon. (AUDIO: The Famished Lands)
Tamsan retrieved the Valeyard after being made aware of his existence and oversaw him being put to work against the Daleks, culminating in him turning a superweapon against them on Grahv and erasing them from existence. After having a vision of the Valeyard fighting the Time War, the Doctor confronted Tamasan at a military outpost and she reluctantly explained what had happened, warning the Doctor not to attempt to breach the time lock the Time Lords had placed around Grahv to imprison the Valeyard. The Doctor disobeyed and stole her TARDIS to break through the lock, much to her annoyance. (AUDIO: The War Valeyard)
When the Daleks began to return to the universe at the Gulf of Ithon, Tamasan was part of the Time Lord forces commanded by Cardinal Rasmus fighting against them. She infiltrated the Time Strategist's enclave outside of time, encountering the Doctor there, and planted a bomb only she could deactivate. The Doctor used her bomb as leverage to make the Strategist let him contact Rasmus and Bliss, getting them to allow Davros to be captured which he correctly assumed would cause a schism amongst the Daleks. With the Strategist paralysed by the competing variables, Tamasan and the Doctor were able to escape to her TARDIS, carrying a stasis pod containing Alex Campbell. She reunited with Rasmus and informed Bliss the Doctor was loading his cargo onto his TARDIS. (AUDIO: Restoration of the Daleks)
Tamasan contacted Ohila about the newly-regenerated War Doctor's recovery on Karn, though their conversation quickly became heated. When the War Doctor demanded to speak to Commander Sanmar's superior he was put through to Tamasan. Tamasan denied all knowledge of Sanmar's plan to extract the heart of Karn. After Sanmar was dealt with by the forces of Karn, the Doctor threatened to use her equipment to destroy the planet to take down an enemy-controlled war front, forcing Tamasan to agree to place the planet in a time lock. (AUDIO: Light the Flame)
Tamasan debriefed second-lieutenant Larinus after her mission to rescue Biroc and was surprised to learn about some of the Doctor's actions. She was delighted when Lorinus revealed she believed the Doctor had killed a group of Tharil prisoners out of mercy, believing he finally understood what had to be done to win the War. (AUDIO: Lion Hearts)
Cardinal Rasmus ordered Tamasan to deliver instructions and a message cube to a contact on Atherea, which Tamasan believed was below her. She stowed away on a cargo ship and was annoyed to find the War Doctor was onboard too. He went with her to meet her contact, who was erased from history forcing them to carry out her instructions themselves. Meeting a hidden squad of Gallifreyan soldiers, they learnt about the Daleks' time eradicator assassinations and the Doctor ordered Tamasan to stay behind from their attack on the Dalek facility to avoid her compromising the battle by being retroactively erased. She disobeyed and followed them, destroying the Dalek Time Strategist. This made her crucial to their success, so the Dalek eradicator targeted her. However, the Doctor and the squad commander were able to foil it. After the Doctor erased the Dalek eradicator from existence these events on Atherea were erased, however Rasmus was aware of the alternate timeline and sent Tamasan to Atherea in a TARDIS to congratulate the Doctor. (AUDIO: The Shadow Squad)
After she crashed on Tharius with the Doctor and Case, Tamasan ordered Veklin to stop the War Doctor attempting to save the planet and kill Case, the latter of which Veklin didn't follow. (AUDIO: Consequences) After Veklin took him away from the city, Tamasan came in a Battle TARDIS to take them away, though was forced to leave Veklin behind when a Dalek Observation Squad attacked them. Travelling to a carrier ship, she had the Doctor locked on the medical bay and was annoyed when he escaped and stole a Battle TARDIS to return to Tharius. After he returned with Veklin and Case, revealing he'd allowed the planet to be destroyed, Tamasan watched the destruction. When asked by a Time Lord why the Doctor had let Tharius he destroyed, she noted it was because he was a warrior. (AUDIO: Destroyer)
Tamasan sent the Doctor to a research base over a gas giant to test the effectiveness of a chemical weapon developed there. She contacted him after he awoke from the weapon's effects and protested as he saw to the base's destruction to stop it being used. (AUDIO: The Keeper of Light)
When the Doctor brought the Temmosus back to Time Lord space, Tamasan led the boarding party. Whilst she was dismissive of the Thals, the Doctor used the bomb Time Lords had secretly planted on the craft as leverage to force her to agree better representation for them on the War Council. (AUDIO: Temmosus)
