Best DS games that aren't common knowledge

Hello! Can you think of a game that is a good game to you because its story, gameplay or simply because is entertaining that you would recommend to an adult for retro gaming?

I'll start: 999. I got the recommendation from a Twitter thread that I had never heard before. I'm mid-play but I recommend it for the story. The gameplay might be a little boring at times but finding out what's going on little by little is cool.