As I've said in a different thread, playing anything before LAD isn't critical as it's pretty much a self-contained story but I'd advocate doing so not only because you'll miss some impactful stuff but also because those are absolutely worthwhile games some of which still top LAD overall in terms of story and have the classic gameplay loop.
Yakuza 0 is a must, as is Kiwami 1&2 if you want to know the series' main protagonist and the newly released LAD: Gaiden somewhat ties LAD with Infinite Wealth showing Kiryu's side of things during the events of LAD and his epilogue.
The only downside is Yakuza 0 is on the older engine but pretty much still the best storyline and setting in the series.
The first Judgment game also has a better story than LAD while the sequel has the best combat with a storyline that fumbles a bit along the way.
Judgment is actually more of a successor to the spirit of original Yakuza but with a detective as the main protag.
LAD is a great game but I've been with the series a long time and it feels more like a spin-off than an integral part of the series. Oh, and Adachi steals the entire show anyways so I was more interested in his story than Ichiban's
EDIT: To the above, not every Yakuza is it's own story. 0, Kiwami 1&2, 3, 4, 5, 6 and LAD Gaiden pretty much follow Kiryu's life with many important chars returning along the way. So the majority of them actually follow a chronological order and are heavily tied by the character of Kiryu Kazuma. Only LAD and Judgment feel like entirely separate stories.
Yakuza 0 is a must, as is Kiwami 1&2 if you want to know the series' main protagonist and the newly released LAD: Gaiden somewhat ties LAD with Infinite Wealth showing Kiryu's side of things during the events of LAD and his epilogue.
The only downside is Yakuza 0 is on the older engine but pretty much still the best storyline and setting in the series.
The first Judgment game also has a better story than LAD while the sequel has the best combat with a storyline that fumbles a bit along the way.
Judgment is actually more of a successor to the spirit of original Yakuza but with a detective as the main protag.
LAD is a great game but I've been with the series a long time and it feels more like a spin-off than an integral part of the series. Oh, and Adachi steals the entire show anyways so I was more interested in his story than Ichiban's
EDIT: To the above, not every Yakuza is it's own story. 0, Kiwami 1&2, 3, 4, 5, 6 and LAD Gaiden pretty much follow Kiryu's life with many important chars returning along the way. So the majority of them actually follow a chronological order and are heavily tied by the character of Kiryu Kazuma. Only LAD and Judgment feel like entirely separate stories.
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