crossing field is the first opening song for the Sword Art Online anime, used from episodes 2 to 14. This song was also used as the ending song for episode 1, though it used the same animation as the opening version, but with ending credits. It was also used as the ending song in episode 25, with scenes from various previous episodes. It was sung by LiSA, with the music and composition done by Watanabe Sho. An official English version of the song is included in LiSA's 7th single, Shirushi.