In Assassin's Creed, Altaïr Ibn-La'Ahad's mentor is Al Mualim.
Al Mualim leads the Assassin Order from Masyaf during the Third Crusade. He assigns Altaïr a series of assassination missions after Altaïr breaks the Brotherhood's rules during an early operation in Solomon's Temple. The missions target influential figures in the Holy Land.
The name Al Mualim means “The Teacher” in Arabic and reflects his position as the order's instructor and leader. The character is also known as Rashid ad-Din Sinan, a historical figure associated with the Nizari Ismaili state, although the game uses a heavily fictionalized version.
A common mix-up is confusing Al Mualim with Altaïr's later mentor, who is not a separate replacement character. Al Mualim's apparent guidance becomes central to the game's final revelation about the Apple of Eden.