After his resurrection in the Last Great Time War, Rassilon became the Lord President Eternal, with his boasts of godhood leading other Time Lords to deem him "mad".
Biography
Following his regeneration from a Sicari attack orchestrated by Romana II, (AUDIO: Assassins) Rassilon became disinterested in ruling and tended to delegate to Livia and Mantus in the Capitol, the Eleventh General in the field and the War Ollistra on strategy. He became obsessed with the idea of the Time Lords ascending to higher dimensions. (AUDIO: Deception, Homecoming)
After Susan Foreman's successes with the Sensorites, the Orrovix, and with the capture of a Dalek agent, Rassilon became interested in her. On Susan's return to Gallifrey from 1963 Shoreditch, Rasmus informed Susan that Rassilon wished to meet with her. (AUDIO: The Shoreditch Intervention)
During the ceasefire caused by the Valeyard erasing the Daleks from time, (AUDIO: The War Valeyard) Rassilon ordered the prisoners of war all be kept, regardless of their cooperation, to attempt to learn who the enemy had been. He presided over a session of the High Council in the Panopticon, but had to be evacuated when the Twelve attacked and later ordered all the prisoners she had released from the Omega Arsenal be put back into stasis. (AUDIO: Dreadshade) Shortly afterward, the memory of the Daleks was restored when the Time Strategist restored them to the universe, resuming the Time War. (AUDIO: Restoration of the Daleks)
Rassilon made a proclamation against the growing resistance to his rule, declaring that they would be "exterminated" like vermin. His rhetoric alarmed Livia and his continuing disinterest in ruling was beginning to unsettle Mantus. Livia even speculated that he had come back "wrong" in his resurrection, though Mantus believed this truly was the Rassilon of old. (AUDIO: Deception)
When the Dalek Emperor led a Dalek saucer over Gallifrey, bypassing Kasterborous' defences with Null Zone technology, Rassilon was infuriated, especially by them using former President Romana II as a spokesperson, and ordered the Fifth Battle Fleet to respond. After the Fifth Fleet's destruction, he ordered the General to recall forces for Gallifrey's defence and sent Livia and Mantus into battle in a pre-programmed Battle TARDIS. Whilst the Time Lord forces fought the Daleks he distracted the Emperor by talking to it, laughing at its delusions of godhood. After the saucer's destruction he ordered the Time Lords to drive the enemy out and had Romana and Leela's TARDIS diverted to the Cloisters. There he confronted them, having Romana imprisoned in a pocket dimension to serve as Gallifrey's archivist for all time and conscripting Leela to the war effort. After this incident, Rassilon declared he would be more personally involved in the Time War, beginning by adding a Visionary to the War Council, and proclaimed his hope for a "Final Sanction" with which the Time Lords could one day ascend, even at the cost of the Time Vortex. (AUDIO: Homecoming)
Rassilon took on a more active role in commanding the War effort after those events, making the War Room the centre of his operations. (WC: Gallifrey War Room) He personally oversaw Leela's recruitment and received updates on her mission to Freme with Veklin and the General from Ollistra. (AUDIO: The Last Days of Freme)
Ollistra informed him of the destruction of a research base in the Death Zone, claiming it had been an accident. (AUDIO: The Passenger)
After the loss of hundreds of TARDISes and Time Lords in his assault on Orrison, Cardinal Rasmus hurried to inform the President of his account of events. In doing so he gave Ollistra leverage over him, as she had anticipated him hurrying to the President and threatened to use evidence she’d gathered to expose the full truth to the President if he did not comply with her leadership of the War Room. (AUDIO: Ambition’s Debt)
By the end of the Time War, Rassilon had regenerated again. (TV: The End of Time)