In the Japanese versions of the games Raiden has been voiced by Kenyu Horiuchi,[27] who felt he could understand the character's pain; despite becoming a cyborg, Raiden still acted like a human.[12] Quinton Flynn was selected to voice Raiden in the series' English adaptation by casting director Kris Zimmerman, who had previously worked with him. Flynn remembers having a long time to develop the character, being instructed by Zimmerman to use an older voice from a character he previously voiced. Flynn stated that Raiden was one of his favorite video-game voice characters, and explained a notable difference between his roles in Metal Gear Solid 2 and Metal Gear Solid 4.[28]