It isn't The Black Mages, but decent nonetheless
The guitar should sound less sampled, otherwise this song won't sound any good and you should put more of your own ideas in it. There isn't much point in making a cover if everything is played like in the original.
Put a limiter in the master even if it isn't loud. This way you can safely reach the peak without it distorting or being too loud and if it reaches the peak, you know it isn't too quiet either.
Otherwise, the mix was pretty good. You've got the frequencies pretty balanced (not too much low nor high frequencies etc). The organ rocks, just like in the original (somethings should be kept no matter what).
Listen to the Black Mages version of this song, if someone does this song right, it's them.