The game is a vertical scrolling shooter with anime influenced graphics and set in a cel-shaded world in the near future. Three kind of shooting types are available, including "wide shot" and "1-2-3 laser" and there is also a bubble type of attack. A shield can be used in near-death situations, protecting yourself from enemy shots as well as destroying approaching enemies. A port of Radilgy was officially released for the Dreamcast by Milestone Inc. on February 16 2006 in Japan. Two special editions were also available in Japan from Sega Direct — one with a phone card, and another that was packaged with a refurbished Dreamcast console and phone card.
The game was also released for the PlayStation 2 and Nintendo GameCube in Japan under the titles Radilgy PreciouS and Radilgy GeneriC respectively. Each of these games was the same as the Dreamcast version but also included an extra gameplay mode exclusive to that version only - "Okawari Mode" in Radilgy PreciouS and "Manpuku Mode" in Radilgy GeneriC.
O~3 Entertainment announced that it would be releasing a port of Radilgy GeneriC in North America exclusively for the GameCube under the new title of Radio Allergy in 2007. The cover artwork for the North American release was notable for featuring a "Wii Compatible" tag, reminding that the game could also be played on a Wii. However, the release date was pushed back several times , and was eventually cancelled as of May 31 2007 due to a lack of interest from retailers in stocking GameCube titles from smaller, largely unknown companies
Radilgy is also included in the compilation Ultimate Shooting Collection, under localised title.
Shizuru Kamigusa, whose father worked for a corporation that was developing a remedy for her radio wave allergy, but a terrorist group took over the building where the father lived. With the help of her partner Tadayo, she rode the modified suit Kojiro to recover her father and the medicine.