In terms of chords and melody, Sirens is significantly more complex than the typical song, having above average scores in Chord Complexity, Melodic Complexity, Chord-Melody Tension, Chord Progression Novelty and Chord-Bass Melody.
Sirens has sections analyzed in the following keys: D♯ Minor, and G Major. Click on the linked cheat sheets for popular chords, chord progressions, downloadable midi files and more!