Unstable is the second album by nu metal quartet Tetrarch.

[1] Musically, Unstable is a nu metal work,[2][3][4] with both the album and Tetrarch credited with playing into the genre's revival.

[1][2] Elements of metalcore also appear, from the "intense" riffs on "I'm Not Right" to "Addicted"'s "pure anthemia".

[1][3] Upon its release, Unstable received generally positive reviews from music critics.

[2] Tetrarch Technical Artwork and design