I've owned this game for a very long time--at least a decade, I think--but until now I've never read it cover to cover. Part of that is just because of how incredibly dense the text is. Most people, even if they're familiar with Japan, aren't going to know all that much about the Sengoku period, which differs from the modern idea of Japanese history in a number of ways. Part of that is because, as with most purely historical games, it can be really hard to find an audience that wants to immerse themselves in another period where we mostly do know how people behaved and there can be a nagging feeling that you're playing "wrong" if you don't use the right forms of address for the daimyo's wife or if you fail to bow when meeting a superior on the road, or whatever, so I concentrated my reading on games that were more likely to see play. But having read though it all, I'm glad I did, even if I never run it as written. I can absolutely see why Sengoku gets so much praised lavished on it.
I don't know of any stronger way to put this--Sengoku's setting is Sengoku Japan, to the extent that you could probably use this book to study for a test at a college-level class on Japanese history. There are hundreds of pages of incredibly in-depth setting information on essentially everything you could ever possibly want to know about life during the Sengoku era. Lists of the provinces and major cities of the time. Descriptions of daily life, food, and clothing. Titles and forms of address. Religious rituals. Extremely detailed lists of armor and weapons. A Japanese calendar and list of month names for extra immersion. Tables of random names and name elements. Honestly, even if you hate the system, the book is worth buying for anyone who wants to run a game set in historical Japan, because while there are rules sprinkled in here and there, most of the fluff is just fluff and can be lifted wholesale for use with another system.
In service of that fluff and setting the proper mood, every page has a quote from a historical Japanese figure below it. A lot of them are from the Hagakure by Yamamoto Tsunetomo, but there are a handful of other often-quoted figures as well. Something like:
...those who keep death always before their eyes are strong and healthy while young, and as they take care of their health and are moderate in drinking and avoid the paths of women, being abstemious and moderate in all things, they remain free from disease and live a long and healthy life.
does a lot more to help set the mood than a dry description of the samurai mindset would.
There's a lot of effort given to point out the differences between the popular conception of historical Japan and the reality, too. For example, ramen, sushi, tenpura, sukiyaki, melonpan, and nearly all of the other famous modern Japanese dishes didn't exist at that time, being invented during the Edo period or even later. Wooden floors were more common than tatami, which was used in audience chambers or important rooms, but not all throughout the house. Christianity, and Christian missionaries, were a weak but growing force in Japanese politics, and the tension between Christian and non-Christian daimyo was a real force.
The focus is mostly on historical Japan, but there is a bestiary with a lot of creatures from Japanese mythology for people who want to have a more fantastic game. There's also a section on magic, but in keeping with the historical feel it's all presented as prayers--"magic" is the result of the kami or the Buddhas acting on behalf of those who ask their aid, not like the typical fantasy view of a sorcerer.
There's a lifepath system for making characters, and I mention it here instead of in the System section below because it's entirely fluff. It has a lot of events to help develop each character's story, like having their entire family commit seppuku in disgrace or being disowned by their lord and forced to become a ronin.
Finally, there's an extensive bibliography with dozens of books and probably over a hundred films, and a full glossary of all the terms used in the book. It's easy to see exactly why the information here is so dense if that's the research that Anthony J. Bryant did to write it.
Sengoku uses the Fuzion system, which I knew almost nothing about other than the name. And that runs into the main problem with Sengoku--its organization is awful.
Concepts are constantly introduced before they're defined or explained. I was reading about bonuses and penalties to rolls before I knew what the character attributes were, or indeed how rolls were determined, since the basic mechanic of 3d6 + stat + skill vs. a target number or another character's roll isn't defined until over halfway through the book. The weapons and armor section is before the combat rules. In the fluff section, when it's talking about duels I learn that backing down from a duel costs "2K honor," and I start wondering if Honor is tracked in the thousands so that even small infractions cost points, and maybe bowing at a 50 degree angle instead of a 55 degree angle to the daimyo costs 15 honor. This obviously is not the case, but I had no way of knowing that until later.
There are three given power levels for games: Historical, Chanbara, and Anime. The only difference is the limit on character traits at character generation and how many points beginning characters have to make their characters, however, and some brief guidelines about what kind of traits or level of magic is appropriate for each tier.
Since Sengoku is mostly about ordinary people, a lot of character differentiation is based on skills. Oh sure, there are secret arts and Ki powers and magic, but those are relatively rare, even if ordinary people can spend Ki in much the same way that Luck or Fate points work in other games. Instead, there are an enormous amount of skills, including such luminaries as Go and Falconry and Cosmetics and Lacquering. I mean, I understand that aesthetic appreciation is incredibly important if you're a member of the Japanese Imperial Court aristocracy, but how often is a PC going to roll Silkworm Raising during the game? That's the kind of skill that you take because it's part of your background and then it never gets rolled, but there's no actual differentiation and everything is placed on a level playing field.
There's a huge list of advantages and disadvantages, which are modified by severity, frequency, and importance to the story. For example, Cowardice isn't really a problem for the commoners, but for a samurai it's crippling. This does involve a lot of calculation, including multiplication and division, and while it's all done before game, it seems like it would make character creation pretty complicated. Not to mention that the disadvantages are all of the "get points up front and it's up to the GM to bring them up during play" type, which is almost always worse than the kind that it's the player's job to bring up during play, just because there are more players than GMs, so if the players are incentivized to play up their own disadvantages it takes a load off the GM's back.
Combat, by default, is incredibly deadly. Weapons do an average of 2d6 to 4d6 damage, plus more for the wielder's strength, and the average person can take 15 damage before dying. Armor is absolutely necessary to survive more than one combat. On the one hand, this does model the various "two samurai face each other, both draw and strike, one dies" moments in Japanese media, but it means that PCs will have a rough time in combat without a lot of underhanded strategy, which is incredibly dishonorable for samurai, or a lot of luck.
The special powers list is relatively short and no real guidelines are given for making new ones. Okuden (secret arts) is the longest, and includes stuff like jumping long distances, throwing multiple shuriken with a single hand, parrying by grabbing a sword with the palms as it's descending, and so on. Ki arts has telekinesis, mystical armor, and making someone's senses less acute. Magic is mostly blessings and curses, though there are some overtly supernatural prayers like transforming into smoke for the mountain-dwelling shugenja hermits who are a bit more sorcerer-like. The neat thing about magic is that not every tradition can use every prayer. Shinto priest, who suffer religious pollution from contact with death or blood, can't cure wounds or diseases, for example, and Buddhists priests can't affect the natural world to nearly the degree that others can.
Sengoku as a game system has its problems, and maybe they wouldn't have stood out to me as much if I had been more familiar with Fuzion. The organizational issues would remain no matter what system was being used. The fluff is incredible, though, and it's more than enough reason to read it, especially if you have any interest in Japanese history or want to set a game in ancient Japan. And how many games would have
GMs should discourage players from wanton acts of seppuku.
written in them? Honestly, that kind of attention to important setting immersion should be rewarded, don't you think?