This is Daisuke Ishiwatari going absolutely feral on guitar with a Dreamcast soundchip backing him up. Guilty Gear X Heavy Rock Tracks is the fighting game soundtrack that convinced an entire generation that anime characters should have Iron Maiden-caliber theme songs.
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"Keep Yourself Alive" is Sol Badguy's theme and it rips so hard it basically became the franchise's anthem. "Holy Orders (Be Just or Be Dead)" for Ky is all righteous fury and galloping riffs, the title literally references Maiden.
Then "Momentary Life" drops with this tense, melodic edge for Baiken that just... yeah. Every single character theme goes harder than it needs to. "Liquor Bar & Drunkard" for Johnny is cocky smooth metal. The track names alone are half the appeal.
If you've never heard a fighting game soundtrack that's also a full-blown rock album, start here and don't look back.