Excellent job, this was a lot of fun. A sort of Dodonpachi inspired shmup with a Game Boy twist. The palette and the art are quite nice, the abstractness reminds me of Zero Ranger.
It's tough as nails, and took quite a few tries to get good at a consistent route. The squid enemies with the circular bullet patterns, the boss phase with extra enemies, and the boss attack that fires in rings were all pretty tough.
After I had the route down, I was able to complete the pacifist run on the first shot. A nice little bonus at the end, though it may be easier than the standard mode as the rate that the health of the boss ticks down is fairly quick. I prefer the modern convention of larger bullets, sometimes the little ones here are hard to track.
I thoroughly enjoyed the gameplay and the aesthetics are all on point. I felt a great sense of accomplishment after overcoming the challenge. Really well done!