 In 2008, Supercell continued to release songs on Nico Nico Douga which quickly became popular. Supercell's releases of "Koi wa Sensō" (恋は戦争) on February 22, "World is Mine" (ワールドイズマイン, Wārudo izu Main) on May 31, and "Black Rock Shooter" (ブラック ★ ロックシューター, Burakku Rokku Shūtā) on June 13 all received over 1 million views. Ryo composed the song "Kibō no Neiro" (キボウノネイロ), released as a limited edition image song CD with the fifth volume of Shū Shirase's light novel series Oto × Maho on July 15, 2008. The song was released in two versions: one sung by Hatsune Miku sold at Animate and one sung by the human singer Sari sold at Comic Toranoana. At Comiket 74 in August 2008, Supercell released the independent self-titled album Supercell containing their most popular songs in addition to several previously unreleased tracks. On December 12, 2008, Supercell released "Hajimete no Koi ga Owaru Toki" (初めての恋が終わる時) on Nico Nico Douga, which has since received over 1 million views; this was the last song Supercell posted to the website.
