is a racing arcade game developed by Sega AM3 and published by Sega. It was first published in Japan in October 1990, followed by an international release for arcades in February 1991. Rad Mobile was Sega's first 32-bit game, using Sega's System 32 arcade system board. It was also the first appearance of Sonic the Hedgehog, who appears as an ornament hanging from the driver's rearview mirror. The game was ported to the Sega Saturn in December 1994 under the name A similar game with a two-seat cabinet, was also released in 1991 as Rad Mobile received mixed reviews; critics praised its 3D visuals, but criticized its gameplay. Gameplay and development Similar to Turbo OutRun, the concept behind Rad Mobile is a race against opponents across the United States. Players must race across the country while also avoiding police cars. At certain points in the race, the road forks, allowing players to skip several stages. The game's weather and time of day changes, sometimes requiring players to turn on windshield wipers or headlights. Rad Mobile was also the first appearance of Sonic the Hedgehog, appearing as a decorative item hanging from the driver's rearview mirror. Sonic's appearance in the game predated his debut in Sonic the Hedgehog for the Sega Genesis by eight months. Interested in getting their new character visible to the public, Sonic Team approved of his appearance in the game. Credit is usually given to Yu Suzuki and his Sega AM2 division, the developers of Out Run, which established the formula of Rad Mobile's gameplay but Suzuki has not listed it in any of his official lists of works. Zach Whalen, an associate professor with the University of Mary Washington, located a segment of text in the game's source code suggesting that Sega AM3 was the actual developer of the game. In a 1991 interview, AM3 head Hisao Oguchi made mention of AM3's involvement in Rad Mobile's development. Sega's AM4 division, at the time a designer of arcade cabinets, had involvement with constructing the game's deluxe cabinet that would bank and turn, and featured functioning brake lights, while the game was also released in an upright cabinet. Release The arcade game was first published in Japan on October 3, 1990, at the JAMMA Show. Rad Mobile was Sega's debut of its System 32 arcade system board, Sega's last arcade board to utilize sprites in place of 3D