https://ferrantepescara.itch.io/alien-invasion
Aliens are trying to invade earth and you are the last line of defense. You will need skill and good reflexes in order to survive, but maybe doom is inevitable?
Can you set a high score against the relentless invaders?
Alien Invasion is a classic arcade style shoot-em up with an increasing difficulty curve.
If you have a flash cart or some other way of placing Game Boy ROMs onto a cartridge, you can also play it on a physical Game Boy. In my opinion this is way better, both for button mashing and for the sound.
Source: itch.io