Blue Rider

Blue Rider is a knight who saved Geronimo Stilton from the Band of Seven Thiefs. He describes himself as: "The best of the best." Geronimo met him on his sixth journey to the Kingdom of Fantasy, finding him as a bit of a braggart when he first met him. At first, he wouldn't let anyone know who he was or where he came from. But at Sapphire City, it was revealed that he is the son of Azul. Blue Rider was shocked to find out that Music Mouse (Geronimo's disguise) really was Sir Geronimo of Stilton. He is Tenderheart's match, due to the birthmark on their forehead in the shape of a little blue heart.

He appeared briefly in Geronimo's seventh journey at Crystal castle after Geronimo retrieved all seven charms from all seven guardians.

Later, at Happy Trails Station in Enchanted City, Geronimo met Blue Rider again, and he kindly gave Geronimo his armor, his cape and a bag of gold. Although Badbeard the pirate took his armor from Geronimo, Blue Rider was in full armor (apart from the helmet) when he returned to form 'The Come Back Club' to rescue Blossom.