The general conceit for most stories set inside of MMORPGs is that people become so engrossed in the game worlds that they almost can't tell that they aren't real. That's the conceit behind both Sword Art Online and Log Horizon, the joke in Paying to Win in a VRMMO, and you could even argue that the kids in Accel World are suffering from something similar. Sakon Kaidō's Infinite Dendrogram isn't all that different in its approach to the isekai subgenre at first, but the author combines bits and pieces of those other franchises in a way that makes things interesting once again, even if this is the 9th iteration of the same basic plot you've read before.

This is largely accomplished by the way Infinite Dendrogram uses its NPC cast members. While the Log Horizon franchise gives us the strong implication that its NPCs were living their own lives in a parallel world that the players simply accessed as a game, Infinite Dendrogram gives its game denizens that humanity from the get-go. The AI is such that everyone appears to live, think, and act according to the same governing principles as the players, with the one exception that players can return from apparent death while the death of an NPC is forever. These NPC deaths can have lasting impact on the way the game itself is played – no one respawns when a quest is complete, so when a neighboring country kills the king of Altar, the kingdom is left without a ruler and is subject to the chaos that comes with it. It's not so much a “game event” as something that has happened within the game's world that has major fallout for the players. Likewise, NPC-based quests change depending on what the players do: buying out a specific item on any given day may trigger a variety of quests from NPCs who were planning on using that item in their daily lives.

That makes Infinite Dendrogram feel much more like a real-world fantasy adventure than a video game one. It's an interesting conceit that largely works to make at least the first novel stand out in its crowded subgenre, but it's also behind one of the book's biggest problems – Kaido's tendency to overexplain what Reiji is experiencing as Ray in game terms. While certain explanations are certainly necessary so that we understand the basic game mechanics, the narrative stops too often for things like the way NPCs function, game and leveling methods, and job options; the fact that each of these are re-explained in almost every chapter results in the reader feeling like they could skip swathes of text, which is never a good plan. While this is likely a holdover from the book's original appearance in serialized format (we certainly see a similar effect in long-running novel series in English), it holds the book back from being as engrossing as it could be.

That's really too bad, because there's a lot of intriguing stuff going on. Reiji (or Ray as he spends most of the book) doesn't feel like an overpowered character – he's obviously new to the game and finds some of its mechanics and options very weird. He does have a particularly special “embryo,” which is an in-game device personalized to each user that basically functions as a super-weapon based on the player's style and thoughts, but Nemesis plays more as a partner than a cheat. Nemesis manifesting as a girl who can transform into weapons definitely helps Ray out as he tries to navigate the playing field, but because she evolves with him, she's only a little more informed than he would be. The culture of PKing within the game is also interesting, as there are specific taboos against killing the NPCs in line with their status within the game world, and it'll be worth keeping an eye on the Alice's Adventures in Wonderland themes that are slowly becoming evident as more about the base AI is revealed.

As some readers may have noticed, “dendrogram” is a type of tree (branching) diagram, frequently used in biology and genetic studies. That will almost certainly come to be important the more we learn about the AI in the game, and the way that the players are already seen to be affecting the game world almost implies some kind of social engineering experiment disguised as an MMO. While there are no clearly sinister motives yet, I wouldn't be surprised to see a few pop up, as the presence of characters named after aspects of Alice in Wonderland could mean that the game itself is some kind of rabbit hole.

With a typo-light and readable translation, Infinite Dendrogram is off to a good start. It may take another book or two to really get to the meat of the story, but there's sufficient pull here to make you want to see what happens next. It isn't entirely unique within its subgenre, but it looks like the story has a few interesting directions it could grow into.