This is an NGADM 2015 review.
This is a great RPG-sounding piece. I have to praise your melodies, and how you keep things going at a steady, consistent pace, but without repetition. You're creating a theme that repeats itself in many different ways and incarnations but without stagnation. In a lot of ways this is absolutely perfect for a game soundtrack, because you've got this continuous feeling where the song isn't broken up into sections but also isn't repetitive. I'm finding it difficult to get tired of it. That, and it even loops! Good lord. This is so fantastic because were I listening to this while playing a game and not really paying attention to it, it'd be difficult to tell when it looped; where it ended and where it began. This creates the illusion of a very long, very complex song that almost always surprises you no matter how many times you've heard it. I love it. In many ways, it's the conceptual holy grail of looping soundtracks.
The production side of things is pretty good, too. Your mix is pretty well balanced, there are very few instances where anything is too loud or quiet specifically. I think the mix lacks power, partially because of the percussion (I think instead of the rapid militant snares you'd be better off with bringing your deeper, tom-based percussion to the forefront; but that's more of an opinion.) The only instance that stuck out to me in terms of mix/balance was the section from 2:33-2:55. Almost everything, but especially the brass, felt too quiet there. I feel that it was probably intentional to pave the way for the semi-crescendo toward the end, but the change in level is definitely perceptible to me and felt a bit odd.
Anyway, I can't really say this song has any real flaws. I don't like the choirs at 2:45, I think they're used improperly and sound a bit digital, and I didn't think the hats in the intro were thematically appropriate at all, but honestly those are such tiny opinion-based problems that I only mentioned them because there's just about nothing negative to talk about. Most of what I've said already has been pretty subjective or mentioned in johnfn's essay :P
You've got yourselves a nicely self-contained, incredible piece here. Keep at it, dudes.