All these 3 tracks are related by common ideas and themes, yet each is very individual. However, they all serve similar purposes.
All three tracks are related by a dark, long mid-range stab that moves across the stereo field, as well as a dark, non-intrusive vocal (guessing that has come from Plex's wife). This signifies the dark atmosphere and theme of this 3-tracker.
Mutant Dx has a melodic arpeggio that repeats throughout the song, which is modulated in frequency, resonance and timbre in thoughtful ways to build tension, as well as maintain interest. The song keeps building to a point near the end at which point it releases its tension and then slowly comes to an end.
Mutant Moog is a darker cut, and most of the work is done by the arpeggio. The Moog really does sound great in this track.
Mutant Disco is a peak time track. It is slower than the other two, yet shares a few similarities to Mutant Dx. It has a similar bassline, white-noise based closed hats which have their release times appropriately automated, as well as a clap pattern where the second clap in every 4 bars is significantly different from the other claps. It has these funky bass stabs that go down in pitch; these add a lot of interest to the track.