The Pokemon Mystery Dungeon games are interesting offshoots of the mainline Mystery Dungeon titles. They make clear a stark difference between primacy and popularity: if you only care about sales, then there is no question that Pokemon Mystery Dungeon games are the main games, because their sales vastly outweigh the other games. The games in the second generation, Explorers of Time/Darkness/Sky, are the best-selling Mystery Dungeon games of all. You have to know that there’s around 30 other games, many much older than the Pokemon flavor, in fact older than Pokemon itself by three years, to know the whole story.
Yet the PMD games are still Mystery Dungeon titles, and they play very similarly. They’re graphical roguelike dungeon-crawl games, just, you, your teammates, and your opponents are not generic fantasy creatures, but Pokemon. That is, specific fantasy creatures. Trademarked ones, in fact.
Because PMD’s fairly popular, you’re more likely to find investigations into its internals than the Shiren or other Mystery Dungeon games, just from the number of people who exist in its audience with both the will and skill to investigate. Yet, those internals are close enough to the MD standard that they even provide insight into how classic Mystery Dungeon operates.
YouPotato TheZZAZGlitch’s usualy video stomping grounds in Pokemon, but they have a fondness for PMD, so they’ve made a video on how the first generation (Red/Blue Rescue Team) generates its dungeons, and what do you know, many of these floor types are also very familiar to me from my time exploring the Shiren games, and it doesn’t seem a stretch at all to presume they’re run by the same, or at least a very similar, algorithm.
And YouTuber Some Body (who has a low number of subscribers, maybe folk should send them some love?) has two videos explaining how the AI in those games works. The first is of more general (well, less niche) interest (the one above), while the second is more about covering exceptions and edge cases.