What is the name of Ezio's hidden blade maker in Assassin's Creed II?

Leonardo da Vinci is Ezio's hidden blade maker in Assassin's Creed II.

Leonardo is portrayed as Ezio's close friend and an inventive ally in Renaissance Italy. After examining an Assassin Codex page, he repairs and improves Ezio's hidden blade. He later helps translate Codex pages and develops additional equipment, including tools that support Ezio's missions.

The game uses the historical Leonardo da Vinci as a fictionalized participant in its secret history. The real Leonardo was a painter, engineer, scientist, and inventor who lived from 1452 to 1519. The game's version borrows his documented reputation for technical creativity while placing him inside the fictional Assassin-Templar narrative.

Niccolò Machiavelli and Lorenzo de' Medici also appear in Assassin's Creed II, but they fill different roles. Machiavelli becomes an important Assassin ally, while Lorenzo is a Florentine statesman connected to the Medici family. Neither is Ezio's hidden blade maker.