Neon Genesis Evangelion: S² Works is a soundtrack box set of music from the anime TV series Neon Genesis Evangelion and the first two Evangelion films, Evangelion: Death and Rebirth and The End of Evangelion. It was released on December 4, 1998 with the catalog number KICA-421/6. It peaked at number 38 in the Oricon album chart, making 2 appearances in total. It was distributed by King Records and composed mostly by Shirō Sagisu. In addition to tracks included on earlier Evangelion soundtracks, this 7-disc set includes many unused songs and alternate mixes or arrangements of existing songs. It was issued as a limited edition release, with only 10,000 copies made. The title is based on the fictional organ that was the power source of the Angels called the S² Engine.