only my railgun is the first opening theme of the Toaru Kagaku no Railgun anime. It was first introduced in the first episode of the anime as an ending theme (initial TV airings only) and from the second episode up to Episode 14 as an opening theme (used in the first episode as the opening theme as well), it was replaced by LEVEL 5 -judgelight-. On the 12th and 24th episode of the anime, it was used as an insert music.

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Hard