Nemesis

The same basic gameplay loop of the mainline Gradius series - a game where you can choose to detonate a linearly increasing power-up bar at different intervals to change to different weapons - with some hitches.

For one, the game itself is not spectacularly pretty, and it has a well-below average framerate for a game of this type. We're talking like sub-20 when most games on the system run at 40+. To be fair, there is a ton of enemies on the screen, but it still detracts pretty sharply from the experience of what is already a fairly slow game.

The gameplay itself is still fun. It's less mindless than the average shooter simply by way of allowing for player strategy at all times on top of normal twitchy reflexes. The soundtrack is pretty good as well, which adds to the "being hunted through space' vibe. The checkpoints are pretty generous but you do have limited lives so it's not a trivial experience.

I think this game is really well designed, but it simply doesn't run well on the Game Boy. I think the NES series is probably the best way to play this, maybe the arcade originals on MAME. Definitely for collectors only.