Super Mario RPG
So we enter the top half of the Top 50, the 25 greatest musical pieces in video game history. OK, my video game history. If you disagree, go ahead and draw up your own Top 50. I'll read it.
It's unexpected that a whimsical game like Super Mario RPG would come up with such an aggressive piece of music as this, but this is the Very Definitely Final Dungeon, Junior, and shit is real. It's an alien world... you know, I spent the entire damned game assuming the giant sword stuck in Bowser's Keep was Smithy. Turns out its name is "Exor" and it's some kind of mystic portal that connects Planet Mario to Planet Smithy. So when you kick Exor's ass you gain entrance, through his giant sword mouth, to Planet Smithy. This is the overworld music on Planet Smithy, where the factories churn out poorly-made mechanical monsters 24 hours a day. Or however many hours are in a day on Planet Smithy. Assuming they have hours.
After the happy fun time Disney Land that was Nimbus Land through Bowser's Keep, this music actually hits you in the face pretty hard. It's high pressure the rest of the way. And this music stands up really well on its own, and is a worthy addition to any mp3 player playlist.