He then takes Astro in as his own and treats him gently and warmly, becoming his legal guardian. He soon realizes that Astro has superior powers and skills, as well as the ability to experience human emotions. Astro then is shown fighting crime, evil, and injustice using his seven powers: 100K horsepower strength, jet flight, high intensity lights in his eyes, adjustable hearing, instant language translation, a retractable machine gun in his hips, and a high IQ capable of determining if a person is good or evil. Most of his enemies are robot-hating humans, robots gone berserk, or alien invaders. Almost every story includes a battle involving Astro and other robots. In one manga episode, Astro takes on the US Air Force, and stops it from bombing some innocent Vietnamese villagers (this was a time-travel episode, in which Astro went back from the 21st century to 1969). The "Astro Boy" series consists of several storylines. Atom (known as Astro Boy or just Astro in English) originally appeared as a supporting character in the Tezuka comic "Atom Taishi" ("Ambassador Atom", sometimes referred to as "Captain Atom"), which appeared in "Shonen", a monthly magazine for boys, in April 1951. Tezuka then created a comic series in which Astro was the main character. According to Schodt, Tezuka created Astro to be a "21st-century reverse-Pinocchio, a nearly perfect robot who strove to become more human and emotive and to serve as an interface between man and machine." As Tezuka's art style advanced, Astro Boy "became more modern and cute" to appeal to his audience of boys in elementary school. Schodt added that the page layouts used in "Astro Boy" episodes "became more creative." When designing supporting characters, Tezuka sometimes created characters that were homages to Walt Disney, Max Fleischer, and other American animators. In several of the "Astro Boy" stories, the first few pages were in color. Tezuka had a "Star System" of characters where characters from his other works played various roles in "Astro Boy". Similarly, several characters in "Astro Boy" appear in his other works. Tezuka developed "a type of dialog with his readers" since he developed so many stories during his lifetime. Tezuka also had a habit of introducing nonsensical characters at random moments in order to lighten a scene which was becoming too serious; he sometimes felt trapped by the need to satisfy his young male audience's desire to see battling robots.