Diego de Alvarado was a member of the Spanish Brotherhood of Assassins who led a Bureau in Burgos before defecting to the Templars and the Spanish Inquisition. By acting as a double agent, he was able to help Grand Inquisitor Tomás de Torquemada acquire one of the three sections of the Staff of Eden for Torquemada.
Subsequently, he assassinated Gustavo Ramírez, one of Torquemada's Dogs of the Lord, at Santiago de Compostela Cathedral when the Assassins confronted the two of them. He declared that his allegiances was neither to the Assassins nor to the Templars but that he would present it to Torquemada for his own rewards. He then fled to steal the last piece of the Staff at the University of Salamanca, where the Assassins had hidden it. After giving Torquemada these two sections, allowing him to complete the Staff, he hid out at ruins in the countryside. Though his camp was heavily-guarded, it failed to deter the three Assassins he infiltrated it and assassinated him.
In the late 15th century, Diego was placed in charge of leading a bureau in Northern Spain, particularly in Burgos, where most of the Spanish Assassins including Aguilar de Nerha were unfamiliar with.
After the fall of Granada and the recovering of the Apple of Eden by Aguilar in 1491, the Mentor attempted to contact Diego for leads on the Templar Gustavo Ramírez's whereabouts, whom the Assassins believed to be in northern Spain. However, Diego was captured by Ramírez, who 'tortured' him for information on another section of the Staff of Eden. Ramírez was able to convince Diego to support the Inquisition and work as a double-agent for the Templars instead.
This led Diego to reveal the whereabouts of the last section of the Staff, allowing Ramírez to continue his search. As the Assassins arrived, Diego maintained his façade as a member of the Brotherhood and directed Aguilar and the Assassins to Sahagún for leads on Ramírez' whereabouts.
Sometime later, Diego travelled to Sobroso Castle, where Ramírez had recovered the last section of the Staff, rumored part of the golden staff of Saint James. The Assassins arrived too late, witnessing Diego's betrayal and Ramírez retrieving the piece. Before they could confront Diego, they were stopped by del Salto, one of Ramírez' lieutenants.
Alvarado then went to the cathedral of Santiago de Compostela in order to give Ramírez the piece of the staff in his possession, the Assassins following. While the Inquisition lieutenants readied to fight them, Alvarado stabbed Ramírez in the back before fleeing. He then went to the the University of Salamanca, where the Assassins had sent the second piece of the staff to be guarded. Alvarado took the piece by force and fled before the Assassins arrived.
He would then deliver the pieces to Tomás de Torquemada and hide out in some old ruins between Salamanca and Ávila. There the Spanish Assassins finally cornered him and beat him in combat, ending him for his betrayal. In his final words, he revealed his final treachery to his former brothers.
- Assassin's Creed: Rebellion – The Fall of Granada
- Assassin's Creed: Rebellion – The Rescue of a Northern Ally
- Assassin's Creed: Rebellion – Sobroso Surprise
- Assassin's Creed: Rebellion – A Brother's Betrayal
- Assassin's Creed: Rebellion – Higher Education
- Assassin's Creed: Rebellion – Pieces of Silver