Oh yeah, I remember who pheidippides was, he was the messenger who ran all the way from Athens to Sparta and then back, and then died suddenly of exhaustion just after yelling "Nike!" the greek god of victory.
Anyway, I really love what you have here. You are extremely improving with your melodies, chords, and rhythm. What really made me attached to this song is the 8bit part at around 3:19. I absolutely love your synths there; especially that short plucky arpeggio at the beginning of every few bars. If I'm correct, (I recognize because I've done it before) did you use the serum noise oscillator with a volume lfo? If so, great job; if not, great job as well :) And best of all, it has a very nice contrast, but not too much so that it doesn't fit.
Having said that, I think it has a couple of minor problems. The very beginning of the song, there are the lowpassed chords and the drums. The drums are the main issue in this part, because they, especially the ride, are outlandishly high frequency compared to the soft chords, so i think a simple lowpass filter rising with the chords should do the trick.
At around 1:18, I'm not hearing much low end. I don't know if that was intentional, since the main drops come later, so I don't really know if you were trying to make like a drop or not.
Other than that, there isn't much else that really stands out to me as a problem, so amazing work, man! Can't wait for your next upload :)