斯特凡諾·達巴尼奧內 （Stefano da Bagnone，1418 - 1479）是一名僧侶、雅各布·德·帕齊的秘書及聖殿騎士的成員，他參與了試圖謀殺洛倫佐和朱利亞諾·德·美第奇兄弟兩人的帕齊陰謀。
Stefano da Bagnone was born in 1418 in the town of Bagnone, becoming a monk at some point in his life. He eventually became a member of the Templar Order, and was trained in Rome as a torturer. He was also a secretary to Jacopo de' Pazzi, who hired him to kill Lorenzo de' Medici.
Stefano da Bagnone was one of the conspirators against the Medici family, having met with Templar loyalists in 1478, within the ancient catacombs that lay beneath the Basilica di Santa Maria Novella.
As one of the mutinous conspirators, Stefano gave his blessing to the Templar plan for the immediate takeover of Florence, which was at that time controlled by Lorenzo de' Medici.
With the following morning a Sunday, the Medici family went to High Mass in the Duomo along with a crowd of eager citizens. The crowd hid the Templar assassins until it was too late, as Lorenzo de' Medici's brother Giulianowas stabbed to death by Francesco de' Pazzi, and Stefano rushed to slice Lorenzo's back, severely injuring his target. He fled before Lorenzo's rescuer could kill him and squirreled himself away in Tuscany, still a willing helper of the Templar organization.
While in Tuscany, Stefano sought refuge in the monastery Monte Oliveto Maggiore. Ezio's informants in the countryside of Tuscany gave him the location of Stefano and a new tool for use in assassination.
To this end, Ezio blended with other monks to infiltrate his way inside. As Stefano was dressed in much the same manner as the other priests of the monastery, Ezio was forced to use his Eagle Vision to locate the conspirator; he discovered where Stefano was located as the man explained his beliefs to another priest, attempting to convince him of the nonexistence of God.
Slipping through the small clusters of nearby priests to approach Stefano silently, Ezio killed him with his Hidden Blade, frightening nearby monks into fleeing the area. It was at this point that Ezio used his new tool – smoke bombs – to confuse the guards and secure his escape.
Stefano da Bagnone was cunning and cruel, a great weapon for the Templars as a torturer and an expert at hiding himself from enemies. He hid where he would not be easily found, surrounding himself with innocents that knew not of his true nature. Stefano bore great intelligence and wit which was displayed when the priest disguised his bodyguards as monks. He knew the Assassin intended to locate him and strike him down. He was simply unaware of Ezio's Eagle Vision and had no idea the Assassin would be capable of discerning his guards from the ordinary monks.
Stefano was also a coward. Despite having copious amounts of cunning and treachery, the priest lacked the virtue of loyalty. He decided to run while Francesco fought alongside his more courageous guards. More evidence of this was his choice to hide in a monastery, a place of holiness and of God, believing that the Assassin would have no ability to strike there. Although this plan showed wit and strategic planning, it also displayed signs of cowardice and naivety.
Stefano's white hair was receding to the point of non-existence at the time of his death, leaving a lightly freckled scalp open to the air. His skin was deeply wrinkled with frown lines and age, hands thickly veined. His eyes were light brown and deep-set into his skull, his brow protruding. Stefano's robes were dark brown and inexpensive, typical of a Renaissance priest. They extended to drape the top of his boots, just long enough to make fast pacing difficult. The top of the robes included a large hood, in which Stefano could hide his face from the public. The priest was tall and unbowed from age, though drastically thin.
- Stefano: Now I will see who was right...
- Ezio: Where is Jacopo?
- Stefano: Nothing to fear I suppose...
They meet in the shadows of the Roman Gods...
- Ezio: Ora sei libero dalla paura. Requiescat in pace. (Be free of your fear now. Rest in peace.)
- Historically, Stefano da Bagnone was a priest who tried to kill Lorenzo de' Medici. He found refuge with monks, but was arrested on May 3, 1478. His nose and ears were cut off, and he was hanged from thePalazzo della Signoria tower.
- He is initially shown to be an atheist through his inclusion into the Templar Order, and his open claims that God did not exist, but he was actually unsure of the truth as shown in his final words.
- When Ezio was about to ask the monks in Forlì about Savonarola, they fled from Ezio because he killed Stefano, claiming that "the killer of monks has returned."
- Before his death, Stefano is seen talking to a devoutly Christian monk. However, once Stefano was assassinated, the monk would try to kill Ezio.