While Sega was seeking a flagship series to compete with Nintendo's Mario series, several character designs were submitted by its research and development department. Many results came forth from their experiments with character design, including an armadillo (who was later developed into Mighty the Armadillo), a dog, a Theodore Roosevelt look-alike in pajamas (who would later be the basis of Doctor Eggman's design), and a rabbit (who would use its extendable ears to collect objects, an aspect later incorporated in "Ristar"). Naoto Ohshima took some of these internal designs with him on a trip to New York City and sought feedback by asking random passersby at Central Park their opinions; of the designs, the spiky teal hedgehog, initially codenamed "Mr. Needlemouse", led this informal poll, followed by Eggman and the dog character. Ohshima felt that people selected it because it "transcends race and gender and things like that". On return to Japan, Ohshima pitched this to the department, and the hedgehog was ultimately selected as the new mascot.