|Appearances||Season 1, Season 2|
|Portrayed by||Howard Ryshpan, English, Season 1|
As an unofficial leader in the quest for the cities of gold, Mendoza seems consumed by a desire for riches, although his true nature is revealed time and time again as his concern for Esteban, Zia, and Tao eventually outweigh his dreams of wealth.
On Magellan's famous circumnavigation of the earth, he encountered the baby Esteban on a sinking ship in the waters west of the Strait of Magellan and threw himself into the water from Magellan's ship to save Esteban and Esteban's father, although Mendoza was only able to save Esteban himself, before a tremendous wave separated Mendoza from the boy's father.
Mendoza took the sun crest out of Esteban's medallion, having a feeling that his fate – and the fate of the boy he saved – were inextricably intertwined. Years later, Mendoza made inquries about the medallion and became convinced that it came from the Cities of Gold. During his stay in Barcelona, Mendoza met Esteban and showed him the missing part of his medallion. Mendoza's prediction came true, as Esteban and Mendoza himself saved each other time and time again.
Mendoza might be selfish and cunning, but this trait has meant that he's helped the children out of a few dangerous situations. If it wasn't for Mendoza, the children would have been captured and their quest to find the Cities of Gold would have come to an abrupt halt.
Mendoza is named after the aristocrat Blas de Mendoza from Scott O'Dell's novel The King's Fifth. Blas de Mendoza is himself based off the historical Antonio de Mendoza, viceroy of both Peru and New Spain.