新曲2
It was never released in any form and there are only five confirmed live performances: On August 8 and October 28 and 30, 1997, as well as on May 5 and August 3, 1998. It is also mentioned in FOOL'S MATE #198 (April 1998), where Kyo explains that 新曲2 and 新曲5 were not finished and didn't receive proper titles. 新曲5 would later be known as 藍紫色.
Among some fans, this song is known as Re:birth. It is unknown where this title comes from, but it could have been inspired by "Rebirth", a song by the Japanese rock band Eliphas Levi. They were active during Dir En Grey's early days and released an album called リデルの赤い書物 (Rideru no Akai Makimono) on June 24, 1998. Rebirth is the fourth track on that album, you can listen to it here.
In June 2023, Shinya took to Twitter to confirm that this song was never officially called "Re:birth".