Demon Slayer was easily one of the most popular anime to release in 2019. Viewers were instantly hooked on studio Ufotable’s glorious animation that brought the series to stunning life for twenty-four episodes. But it wasn’t all flash—the story of Tanjiro’s goal to bring his sister Nezuko back resonated with everyone, as the world’s best older brother and cutest younger sister found themselves up against impossible odds that everyone wanted to see them overcome.

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This list is devoted to some of the most shocking reveals in Demon Slayer—but not just in the anime, but in the manga as well. This list will have some major reveals from the manga contained within, so please be warned!

10 NEZUKO REFUSING TO KILL TANJIRO

One of the series’ most shocking moments occurs at the very beginning. After Giyuu explains what’s happened to Tanjiro’s sister Nezuko, things could have easily gone awry; more cynical series would have had Tanjiro be forced to take his sister’s life.

From there we would have wound up with a former Good Boy who was now dead inside, driven solely by revenge to take Muzan’s life. Instead, his emotional appeal broke through, and Nezuko was able to see Tanjiro as her brother, rather than food. She defended him against Giyuu and has proven instrumental in many of his most crucial fights.

9 MUZAN TRANSFORMING HUMANS INTO DEMONS

It was surprising to see Demon Slayer waste no time introducing the lead villain of the series to the protagonist, especially considering how restrictive Muzan turns out to be concerning people hearing about him. Muzan and Tanjiro meet on the street in a crowded city in the middle of the night, but Tanjiro's keen sense of smell makes it impossible for him not to realize who it is.

Unfortunately, Muzan proves capable of escaping with one simple move: Swiping at a human's neck, instantly transforming them into a demon. The ease with which Muzan can do this is so simple that it's a small wonder half the country isn't under his control.

8 LEARNING SOMEONE ELSE KNOWS HOW TO MAKE DEMONS

tamayo wearing a flowery kimono in the demon slayer anime

When Muzan Kibutsuji is first introduced to the audience, it’s with one of the most chilling scenes possible. After Tanjiro spots him, Muzan creates a distraction simply by nicking the back of an innocent passer-by, transforming him into a demon.

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Shortly after that, we learn of someone else capable of making demons: Tamayo. When we meet the nurse, she’s learning the ins and outs of how to cure a transformation into a demon. Tamayo has transformed a single young man, Yushiro, into a demon, who decided to help her out of gratitude. Could this transformation be used for good someday?

7 TANJIRO BECOMING A FIRE BREATH USER

When the series begins, Tanjiro is taught by Sakonji, the previous Water Pillar before Giyuu took the job. He does pretty well with these abilities, though he has a nasty habit of letting his sword get cracked while using it.

During his battle against Lower Demon Five Rui, Tanjiro learns a different set of techniques that fit his abilities better. Remembering his father’s Dance of the Fire God, he taps into an entirely new set of sword stances that allow him to overcome Rui and slice his head off.

6 ZENITSU BEING AWESOME

Zenitsu, unconcious and ready to fight in Demon Slayer.

When we meet Zenitsu, he’s a hapless guy who begs Tanjiro for help because he doesn’t want to die fighting demons. Knowing what the Final Selection entails, most of us couldn’t help wondering how he managed to survive in the first place.

Even while working with Tanjiro during the Drum House arc, it doesn’t seem like there’s anything to Zenitsu at first. But then he passed out and instantly laid out a demon with the Breath of Thunder’s First Style, Thunderclap Flash. For Zenitsu, killing demons is so easy, he does it in his sleep.

5 ORIGIN OF UPPER MOON ONE

Manga readers are still reeling over this one. The Upper Demon Moons have all proven to be incredible challenges—not a single one has gone down without more trouble than the Slayers are prepared for. However, the introduction of Upper Demon Moon One resulted in some truly chilling revelations.

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Kokushibo turns out to be not only a Demon Slayer but one of the oldest members. His powers were the Breath of the Moon style, which was based on the style used by Yoriichi, Kokushibo's brother, the most powerful and first of the Demon Slayers.

4 SHINOBU SACRIFICES HER LIFE

The current arc of the manga has had nothing but shock moments from beginning to end. But one of the biggest shocks was watching Shinobu battle against Douma, the Upper Demon Moon Two.

We learn that Douma was responsible for taking her sister’s life, and afterward, we expect to see her defeat Douma in her sister’s honor. But Shinobu’s plan has nothing to do with her walking away from the battle, and instead, she sacrifices herself to present Kanao with a chance at victory.

3 DEMON SLAYER MARK

The truth is, being a Demon Slayer kinda blows. Though early on it feels like there’s a back and forth between the two sides, the truth is Muzan and his followers are immortal and have access to superhuman powers. But one thing has helped even things out a bit—the so-called demon slayer mark, which comes to Slayers after someone attains a heart rate of over 200 beats per minute and a body temperature over 39 degrees Celsius (102.0 F).

This gives them super speed, strength, and more, though it can only be accessed for short periods of time. With this, hopefully, things have finally evened up enough to allow for a fight the Demon Slayer Corps can win.

2 MUZAN KILLS THE LOWER MOONS

The Natagumo Mountain arc has some of the most terrifying and hype moments of the series. Tanjiro and the gang run into Lower Moon Five Rui, a young child who’s been putting demons under his control and playing family in the forest. When he’s finally brought down by Giyuu, Muzan is enraged.

He has a meeting of all the Lower Demon Moons, insulted that they constantly find themselves losing to the Demon Slayers. While lamenting their worthlessness, he finally gets fed up and one by one kills all but one. Other series might have had these characters serve as stepping stones for the slayers to become powerful enough to face the Upper Moons. Demon Slayer offers no such “training wheel” villains.

1 NEZUKO GAINING POWERS

For most of the series, Nezuko is mostly there as Tanjiro’s motivation to become better. Though she’s helped multiple times during battles to stop Tanjiro from being killed, it’s usually Tanjiro or someone else who strikes the killing blow. But during the Natagumo Mountain arc, Tanjiro winds up facing one of the Lower Demon Moons, and Nezuko gets captured during that battle.

After it seems like Tanjiro is going to die in his battle against Rui, Nezuko reaches a new level of power and activates her first Blood Demon Art, setting afire the webs that would have dissected Tanjiro otherwise.

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