*screen swirls and boss appears*
It definitely sounds like a boss battle theme! It has great energy, good balance in the mix, good instrumentation, and a powerful melody. My qualms are with the composition.
The main melody is repetitive. If this was playing the entire time I was fighting a boss in a JRPG, I would eventually turn the volume down pretty far. That one-measure melody does not have enough variation. Moving that melody up or down in the scale would help vary it a little. Maybe if the track gets more intense and the melody plays up a 3rd or a 5th, that would give it some diversity. If the track mellows out a bit more, maybe it starts slowly building that melody back in but at a lower octave. Along with varying that melody, there should be some varying sections.
Specifically, the song lacks a flow between two distinct levels of intensity. Throughout this track, there is a substantial amount of energy. A great way to mix it up, would be to transition to a more mellow section. Perhaps, the percussion is still playing just as fast, but is keeping a more down-trodden beat. At the same time, maybe the strings could fill in the space with some long chords. You have a section that touches on this, but it does not dive fully into that idea. That section has to feel almost like a cooldown, that way it can build the tension back into that intense melody.
I would take a look at the battle music from the Final Fantasy series. I am most familiar with VII so I will reference that. The fight music in that game follows a formula of sorts. There is a strong driving rhythm in the beginning, and as it goes from one section to the next, it keeps building the tension and then releasing just a little bit to build it back up again. There are always softer parts that crescendo back into the intense melodies.
Overall, the mix is great, there is a good balance across the board. Each instrument seems to fill its space in the spectrum and serve its role in the composition quite nicely. Even though that melody is repetitive, it is catchy as hell! Nicely done!
Either way, this is a cool track and you are very talented! Keep up the good work!