In Assassin's Creed II, Rodrigo Borgia is the Borgia leader who becomes the final major target of Ezio's early revenge quest.
Rodrigo is a powerful Templar leader who operates under the historical identity of Pope Alexander VI. Ezio confronts him in the Vatican at the end of the main story, where Rodrigo possesses an important Piece of Eden known as the Apple. The confrontation closes the central revenge arc but does not end the wider Assassin-Templar conflict.
Cesare Borgia, Rodrigo's son, is the principal antagonist of Assassin's Creed: Brotherhood rather than Assassin's Creed II. Juan Borgia is another historical member of the family, while Ludovico Sforza is a Milanese political figure. These related names are common sources of confusion when identifying the game's final antagonist.