In Assassin's Creed II, which Renaissance artist and inventor helps Ezio Auditore?

In Assassin's Creed II, Leonardo da Vinci helps Ezio Auditore as a Renaissance artist and inventor.

Leonardo is one of Ezio's most important allies in the game's historical storyline. He deciphers pages from the Codex, a collection associated with Altaïr, and uses his technical knowledge to improve Ezio's equipment. Leonardo's workshop also provides a recurring place where Ezio's weapons and tools can be upgraded.

The game presents Leonardo as a young man working in Florence and later Milan. Its version of him is fictionalized for adventure, but it draws on his real reputation as a painter, engineer, anatomist, and designer. The historical Leonardo did create designs for flying machines and military devices, although the game adapts those ideas into playable technology.

Leonardo is not Ezio's mentor; that role belongs primarily to figures such as Mario Auditore and Niccolò Machiavelli. He is instead a trusted civilian friend whose inventions connect Renaissance science and art with the series' fictional Assassin conflict.