I’ll nominate Battle Bakraid. Anyone who knows me probably knows what I think of Garegga and Batrider. (They’re 10s Jerry.) Bakraid is better and also much worse. It pushes the formula a step too far into self parody. Casually it’s probably the best Yagawa game to start with. It’s not nearly as punishing as Garegga, it doesn’t have nearly the amount of character juggling and secrets as Batrider. It’d just a cool 7/10 shmup. The second you play for high score though…
You realize that something terrible has happened. You see, Bakraid has a lot of multipliers. You shoot ships in quick succession? You multiply your score by up to 64 times. To compensate for this, the score required to earn an extra life was increased of course. It’s twice as high as in Garegga…which means you’re still earning 32 times as many lives. Unfortunately, dying is very helpful: it extends your multiplier timer during sections without enemies to shoot, it gives you power ups, it gives you bombs, it’s horrifyingly optimal.
So we get a game where scoring runs are constantly dying on purpose. To be fair, Garegga and Batrider have a lot of intentional deaths as well, but here we’re talking literally every 30 seconds, while still doing all that would be required of you to score in a “normal” game.
You either look at this and say “Flow state!” or “No thanks!” and I’m pretty firmly in the “No thanks!” camp. That being said, it is a heck of a thing to watch someone else pull off, just not quite a thing worth pulling off yourself.