I agree. It's almost a hidden gem IMO too. Played the hell out of it when I was younger. Never finished it but might give it another run to try and do that. Thankfully you can mod the NES Classic and I put that game as well the majority of the NES library on it to enjoy.
I really think that a nes game has (almost) never had music as compelling and at the same time exciting as Power blade. The most exciting is definitely sector 3, it really gives you chills to listen to it nowadays. I feel like being transported back to the 90s in my bedroom in front of a crt. How exciting, Natsume gave us some of the greatest titles for nes like Power Blade, Shadow of the Ninja and Shatterhand. Tears fly for those bygone days.
This music just brings back memories when I was playing this game at my classmate's. We were in Grade 5 at that moment and we would get together every Saturday afternoon to share the FC console with 4 people or 5.
I remember hearing another NES game that has a song that sounds super similar to this, but I forget. But, it only sounded like the part from 0:08 to 0:24 or so. Strange. Feel like this song might've been plagarized by another person or maybe I'm just misremebering. EDIT: found it. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-GH_B1R9-_So.html