Demon Slayer: Mugen Train Arc

Demon Slayer: Mugen Train Arc

Demon Slayer: Mugen Train Arc anime series/movie cover art
Demon Slayer: Mugen Train Arc

Arc Overview

Demon Slayer: Mugen Train Arc is the first Demon Slayer movie and takes place after the first season of the series. It’s canon, with the second season taking place after it, which is why I binged it all the day before the second season began.

You might be thinking, “what do you mean you binged it? It’s a single movie.” And, you’re right, to an extent. It is a single movie. But it was also re-released this year as 7 episodes with some additional content. I watched that version of the Mugen Train Arc, not the movie version.

I don’t believe the fact I watched the TV release is going to matter very much as far as this review is concerned. If you’ve seen the movie version, you’ll still know what I’m talking about (for the most part, probably).

Anyway, I thought the arc was very good. But, I wouldn’t say it was very consistent in its quality. For example, there were multiple antagonists for different parts of the arc, and that was a bit awkward. I’ll discuss that more toward the end of this review, though.

As expected from Demon Slayer, the art and animation were extremely good — except for the one, major part where they weren’t. The titular Mugen Train is turned into a giant flesh monster about halfway through the arc, and that didn’t look great.

I get that this is ufotable’s animation style (blending 2D and 3D), but come on. That wasn’t a great way to blend those two styles. And on top of that, as I’ve said in other anime reviews, such as A.I.C.O.: Incarnation, I absolutely hate the giant flesh monster trope.

Giant flesh monsters just don’t make for good enemies. They’re boring and never look good.

Kyoujurou Rengoku

If the giant flesh monster is the worst thing about the Mugen Train Arc, then Flame Hashira Kyoujurou Rengoku is the best thing about it. I know a lot of people really like Rengoku. And so, I went into this arc expecting him to have been extremely overhyped.

Was he overhyped? Maybe a bit. And there are aspects of his character that I don’t like, such as how he says whatever he’s eating tastes good after every single bite. But, as a shounen series, I do expect most characters to have some weird tick like that.

Aside from that aspect of Rengoku’s character, I think he’s great. I love his sense of justice, which we see right in the first episode of the arc. I’m not a huge fan of superheroes. However, I liked Rengoku’s superhero attitude toward slaying demons.

Kyoujurou Rengoku from the anime series/movie Demon Slayer: Mugen Train Arc
Kyoujurou Rengoku

From what I remember of the other Hashira from the first season of the series, they typically don’t slay demons for good. They slay demons for revenge. They hate demons and think they need to be eradicated at all costs. That’s not quite true for Rengoku, though.

Obviously, he doesn’t like demons. But Rengoku doesn’t fight demons in order to eradicate them. He fights demons in order to save lives. He wants people to be able to live their lives without ever fearing that they’ll fall victim to a demon.

And another thing that’s great about Rengoku is that he’s strong enough to back up his noble view of his position as Flame Hashira. Throughout the arc, only one human died once Rengoku was involved — himself.

In the first episode of the arc, he makes his heroic entrance by saving the girl and her grandmother. And in the final episode, he makes his heroic exit by giving his life to save all the train passengers.

An Arc of Two Halves

The 7 episodes of the Mugen Train Arc can be split into two groups. Episodes 1, 6, and 7 are the good episodes, and episodes 2, 3, 4, and 5 are the “bad” episodes. Basically, the arc can be split up based on whether Enmu is the antagonist or not.

Enmu is the demon responsible for the disappearances on the Mugen Train. He’s a member of the Twelve Demon Moons, being Lower Moon One. But the problem with him (I originally thought he was a woman) is that he’s a boring antagonist.

We don’t get a good direct fight against Enmu. Enmu’s fighting style is very passive. He puts people to sleep and then has his human minions enter their dreams to kill them. And, of course, Enmu is the one who turns into a giant flesh monster, so I hate him for that too.

Flame Hashira Rengoku from the anime series/movie Demon Slayer: Mugen Train Arc
Flame Hashira Rengoku

Episodes 1, 6, and 7 have different antagonists. The antagonist of episode 1 was the “Slasher,” or at least I think that’s what he was called. And the antagonist of episodes 6 and 7 was Akaza, whose position is Upper Moon Three.

The Slasher isn’t a great antagonist, but he fulfilled his role of being a minor antagonist at the start of the arc to mark Rengoku’s introduction. And as one of the Upper Moons, Akaza is a powerful adversary for Rengoku to go up against at the end of the arc.

What this means, however, is that after the first episode, I lost interest in the arc until the end. Nothing exciting comes from the whole middle part of the arc. I would have rather had Akaza as the antagonist for the whole arc after episode 1.

Imagine this: Enmu is Akaza’s subordinate who fights against Inosuke and Zenitsu while Rengoku and Tanjirou take on Akaza. The arc still could have ended the same way. But it would have been more interesting than 4 episodes of just Enmu.


Overall, I’d say the Mugen Train Arc was an 8/10, which is apparently slightly higher than what I gave to the first season. Those 4 episodes in the middle definitely had an impact on that rating. If it was just the 3 “good” episodes, it probably would have been a 9.

What do you think of Demon Slayer: Mugen Train Arc? Did you watch the movie, series, or both? Am I being too hard on Enmu, or do you agree he was a boring antagonist? And how do you feel about Rengoku’s character? Let me know in the comments.

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2 Replies to “Demon Slayer: Mugen Train Arc”

  1. According to Author note Enmu was roughly as skilled and powerful as Rui (Lower 5) was. Rui was considered a rising favorite by Muzan with a ton of potential, Rui had even weakened himself a fair amount by dividing his power into other Demons in his fake family. The reason Rui was Lower 5 is because he had no interest in rising in the ranks and so did not challenge any of the ones above him.

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