Which Assassin's Creed protagonist is a member of the Auditore family?

The Assassin's Creed protagonist who belongs to the Auditore family is Ezio Auditore.

Ezio Auditore da Firenze is the central character of Assassin's Creed II, Assassin's Creed: Brotherhood, and Assassin's Creed: Revelations. His story begins in Renaissance Italy after a political conspiracy destroys much of his family, pushing him toward the Assassin Brotherhood.

His major adventures take him through Florence, Venice, Forlì, Rome, and Constantinople. Although he starts as a young Florentine nobleman, he eventually becomes a mentor and a senior figure within the Brotherhood.

Ezio is sometimes mistakenly described as the protagonist of the entire franchise. In fact, Assassin's Creed uses different protagonists across different historical periods. Ezio is the series' most extensive single playable protagonist, appearing across three main games and several related works.