This game is pretty good. I usually hate indie "retro" aesthetics, but I don't get the "indie" feel from it. It feels like a proper tribute to old japanese games. Not specifically because of it's extremely well made sprites, but because of it's well made gameplay. It's tight, fast, responsive, and fun. Also, this is one of the only "retro" indie game that I have played that really has that "umph" factor to it's sound effects, every hit has that crunchy bass which in my opinion is extremely important for games like these and most people fail on doing. You actually feel satisfaction from hitting things, it's very similar to a lot of Genesis games in that regard.
This game is dirt cheap right now during the winter sale so I would go ahead and buy it and spend at least 30 minutes on it, it's pretty fun.
Whoever made this game, I hope he or she doesn't stick with the retro graphics though. It's very very well made but honestly a lot of people probably avoided this gem because most people assume retro graphics = ♥♥♥♥♥♥ indie game, which for the most part is very true.