I can't believe someone actually suggested a loop. That's the cheapest, most blatantly transparent way to add to a song's length. It does nothing to improve on the song, and if the song isn't great anyway, the LAST thing I wanna hear is it repeat itself to drive its mediocrity home.
Anyway, this is not terrible, but it's underwhelming and the sound quality isn't good at all. Seriously, the fact that you didn't loop it helps the score. We all love Zelda, but only the worst fanboys overlook the overworld theme's repetitiveness and wanna hear it 40 times in a row.
I must say, I like this a lot, and metal isn't my first favorite genre. I liked how you started it straight, and then got into the metal, it was a nice prelude. I think it should be longer. Maybe you could loop it once, and then it would be perfect.
You can't find a better mix then Zelda and metal. Maybe longer song would have been better but it's good that way too.
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