The Altered Scale, often referred to as "super Locrian," is one of the modes of the melodic minor scale. It is primarily used in jazz and fusion genres, particularly over dominant 7th chords, to add tension or a more complex sound. This scale is built by altering (or changing) the non-root notes of a dominant scale, which gives it its unique name and sound. In terms of its structure, the Altered Scale includes the root, minor second, minor third, major third (or augmented second), diminished fifth, minor sixth (or augmented fourth), and diminished seventh. In essence, every other note besides the root is altered from the natural major scale. For example, an E Altered scale consists of the notes: E, F, G, A♭, B♭, C, and D. Here, the 9th (F), 11th (A♭), and 13th (C) are lowered, and the 5th is altered to a diminished fifth (B♭). When playing over a dominant 7th chord, such as E7, using the Altered Scale can bring out more chromatic and dissonant textures, adding a sense of resolution and movement that wouldn't be available from a more conventional scale, like the Mixolydian. This makes the Altered Scale a favorite among guitarists looking to add expressiveness and distinctiveness to their solos.