Catastrophe is written in the key of C Phrygian.
According to the Theorytab database, it is the 2nd most popular key among Phrygian keys and the 50th most popular among all keys. The C Phrygian scale is similar to the C Minor scale except that its 2nd note (D♭) is a half step lower. Chord progressions in Phrygian often rely on the major chord built off of this 2nd scale degree (D♭ major) which gives the key its distinctive sound.
See the C Phrygian Cheat Sheet for popular chords, chord progressions, downloadable midi files and more!