 In the 1980s, O'Neill became a large rock promoter in Japan, promoting every tour of Madonna and Sting done in that decade, as well the largest rock festivals done in Japan until that time, with such acts as Foreigner, Bon Jovi, Whitesnake and Ronnie James Dio.Among other bands, O'Neill helmed Aerosmith's "Classics Live I" and "Classics Live II" albums before beginning a fortuitous relationship with the band Savatage that led to conceptual pieces such as "Hall of the Mountain King", "Gutter Ballet", "" and "Dead Winter Dead".It also introduced him to Jon Oliva, Bob Kinkel and Al Pitrelli, as well as reconnecting him with studio engineer Dave Wittman, who all became original collaborators in O'Neill's next group, Trans-Siberian Orchestra.