Though the game bears the name, and the title screen bears the image of the famous french fortuneteller, it's not about him. It's about a war (or possibly alien invasion?) that occurs at the end of the century, which was probably one of his predictions. You know how vague they are. But anyway, this is a shooting game that, as far as I know, has no home ports, and I suspect the reason for that is that in more ways than one, it comes between two eras.
The first, and most relevant way it does this is in the same as lots of arcade games that didn't get home ports. It came out in 1993, and graphically, it's beyond what could satisfactorily have been done on the Mega Drive or SNES, but by the time the Saturn and Playstation came about, it would have been old hat, and it's definitely not a popular or famous enough game to have made up for that. It does look really good, though. There's not much in the way of special effects, but there's a lot of amazing-looking super-detailed pixel art in the backgrounds and sprites alike.
The other way in which it stands astride two eras is less relevant to its unported status, since it's an aspect it shares with games that did get ported to home systems, like Grind Stormer and Batsugun: it's one of those games that bridges the gap between classic-style shooting games and later danmaku-style shooting games. There's never super-elaborate or particularly dense bullet patterns, but there is still a fair few enemy bullets coming your way from very early in the game. Furthermore, while you don't have a screen-clearing, bullet-cancelling bomb, you do have a charge shot that, when being charged, manifests as a small energy field following your ship around. This energy field does cancel enemy bullets, so with a bit of skill, you can maneuver around in such a way that it keeps you safe. Of course, that means you aren't shooting, so you aren't killing enemies or revealing the score items that remain invisible until you shoot their hiding places. (I almost called this a danmaku shooter thing because of the hidden bees in the Dodonpachi games, but then I remembered that it's something that goes as far back as 1986's Star Soldier).
Something else that's of interest is that the bosses have a unifying theme of modularity. That is to say, each boss is made up of various smaller parts that come together to form the whole boss. What's interesting about this is the way that sometimes you'll destroy one of a boss' constituent parts, and a different one will fly in, and attach itself to the core and give it a new set of attack patterns. Sometimes, you'll fights some of the segments during the stage as larger enemies that escape before you destroy them, then they come together at the end of the stage to form a boss.
Another aesthetic quirk I'd like to mention is that, as well as the in-game graphics looking so good, there's a fair bit of thought that's clearly gone into the game's overall presentation, with the aspect I'd particularly like to highlight being the player characters. There are two characters, though you unfortunately can't pick which one you get: player one is always Dalas (sic), and player two is always Joanna. I don't recognise them, but their faces on the screen that appears after you insert a coin really look like they must have been traced over photos of real people. There'sa possibility that the developers actually hired models themselves, since there's different pictures of the pair on the high score screen, this time in profile. Dalas has a lit cigarette in his mouth in both situations, of course! I wonder if there were plans for more to be done with these characters?
Nostradamus is a pretty good shooting game. It won't blow your mind or change your life, but it's still fun enough, and worth pushing through the high level of difficulty to see more of the beautiful pixel art it contains. Luckily, even the animation for your ship exploding looks great!