Altaïr Ibn-La'Ahad is the Assassin's Creed protagonist who serves as a Levantine Assassin during the Third Crusade.
Altaïr is the central historical character in the first Assassin's Creed game. He is an Assassin based in Masyaf and operates across cities including Jerusalem, Acre, and Damascus. After a serious failure during a mission, he is demoted and must regain his status by completing assignments for his mentor, Al Mualim.
The character's name is often written with a different apostrophe or transliteration, but “Altaïr Ibn-La'Ahad” is the commonly used English form. Ibn-La'Ahad means “son of none” in Arabic transliteration. Altaïr is distinct from Ezio Auditore, who leads Assassin's Creed II and several later games.
His story also establishes the series' recurring theme of historical memories being explored through the Animus. Later games revisit Altaïr's life, especially Assassin's Creed: Revelations, which connects his legacy to Ezio's story.