Yakuza Zero:
This was the Yakuza game that started it for me. i never consider the Yakuza games during their initial release periods growing up. I was very much "JRPG or bust" back then and it's a real shame because the Yakuza series is a JRPG and I was too stupid to know any better.
I picked up Zero at first when Yahtzee talking about it on a Zero Punctuation video and thought it would be a good place to give the series a try. But I didn't. In fact I didn't play Yakuza 0 until Covid lockdowns and FF7 got delayed a few weeks. Even then I didn't play Zero. I played Like a Dragon or Yakuza 7, which had actually become a JRPG, and I fell in love with the craziness of it all, this urged me to go back and play Zero, and thus the chain continued until I'd played them all except the Zombie on and the Japan only one (which is out now so that'll be fun).
Yakuza games are interested because they always take place in the time frame when they release in the real world. The original game took place in 2005, and Yakuza 7 took place in 2018ish. But with Zero they couldn't do that, but they managed to time-capsule the game anyway by setting it in the 1980's during the real estate boom in Japan, where the economic bubble was going crazy. We take control of Kazama Kiryu again only he's a green in the tooth kid who is still and unstopable badass, but nobody knows it yet. Kiryu is hired by a loan shark to rough up someone who owes money in a specific alley. Turns out the alley is an empty lot that the Yakuza clans really really want, and it turns out that Kiyru's beatdown resulted in death for his victim, except not really. Kiryu is framed and by making a crime scene take place in the empty lot everyone wants, aquiring the lot gets more complicated.
So Kiryu is sent to jail for the first (but not last) time. Someone set him up in order to make his mentor, a leader in the Tojo Clan, look bad and thus using that as leverage to move up in ranks. Kiryu gets out of prison with the sole goal of finding out who set him up and who's after his mentor.
Meanwhile crazy Goro Majima is...not crazy at all...in fact Goro is running a very popular hostess club. And for long time fans this is really jarring, knowing how Goro is the rest of the series. Goro here is laid back, calm, but also strong and sure of himself as well, nothing like what he eventually becomes. Turns out Goro owes people a lot of money, and they set him up as a Club Manager to pay back the debt and to be allowed to return to the Tojo clan. He is also very close to paying this debt off until the man in charge of that debt reminds him that there has been interest building up and he's nowhere close to paying off his debts.
But no worries because Goro is offer a deal. All he has to do is assassinate someone. Now if you've played Yakuza games before, you'll know that in these games the Yakuza don't shy away from crime in any way, except when it comes to killing people. Murder is super serious and most of the time they always try to avoid it. So Goro being offered a return to the Yakuza through murder is a pretty deep twist.
What Zero does so brilliantly here is it takes two very different people with two very different goals somehow manage to both circle back to the empty lot. It's done so well with such great twists that I would argue that Zero has the best mainline story in the franchise.
Zero's combat is also not only really good but also fits into the themes of uncontrolled wealth during this time period. Both characters have stances like they did in Kiwami 1, and each stance has a speciality and a talent tree used to make it stronger. However unlike other games where it's a matter of experience points and levels, in Zero all the skills are bought with cash. Cash rains from the sky in this game where being a Billionaire means you're still pretty poor. By the end of the game both character will spend 100's of Trillions in Yen to unlock skills as well as progress their mini games.
The big mini games in Zero are fantastic two, but Goro's mini game is better than Kiryu's easily. Goro gets a Host Club where you must learn hand signals and glame up your girls to make money in a Host Club tournament. It's a management game that has you assigned girls to the right customers to fit personalities together in order to get people to spend as much as possible. Whereas Kiryu's mini game is basically going around town and buying up all the businesses, then having money fights with leaders of specific zones in the city. It's fun and it makes you a shitload of cash, but it isn't as engaging as the Host Club.
Yakuza 0 all in all is probably my second favorite of all the Yakuza games so far. But I disagree that it is the best introduction to the series for people. Personally I think Kiwami 1 is the best place because a lot of Zero's surprises lean on player knowledge of future games. Without knowing about Goro for example, the impact of his personality and circumstances in Zero is lost on a new player.