Demon Slayer’s Yoriichi Type Zero and 300 year-old sword explained (2024)

Demon Slayer season three spoilers follow.

Season three’s second episode just ended with a major cliffhanger. We watched Tanjiro spend most of the episode battling against an extremely cool mechanical doll, the Yoriichi Type Zero, under the tutelage of young swordswmith Kotetsu until the pair were surprised by a treasure hidden inside.

After Tanjiro was able to dodge a particularly lethal attack and knock the doll’s head clean off, it was revealed that the mechanical body was actually home to a mysterious sword.

But whose sword is it? And who exactly was the swordsman from 300 years ago that this killer doll was based on?

Let’s take a look at the answers to Demon Slayer season three, episode two’s biggest questions, but beware – there are significant manga spoilers ahead.

Related: Demon Slayer spin-off gets exciting update

What is the Yoriichi Type Zero mechanical doll and who built it?

During episode three, we learned that the Yoriichi Type Zero was built by Kontetsu’s ancestors more than 300 years ago during the Sengoku era.

The doll was intended to train Demon Slayers, who regularly travel to the Swordsmith Village to fix and acquire the Nichirin Swords they use to behead and deal with those pesky demons.

Kotetsu tells us the doll was modeled after a famous swordsman, whose skill was so impressive that it could only be simulated by giving the training dummy six arms. Talk about a handful.

Fans who’ve dipped into the Demon Slayer manga will recognise the doll’s face as belonging to a significant supporting character called Yoriichi Tsugikuni. Plus, eagle-eyed anime viewers will definitely recognise him from Tanjiro’s coma dream in the season three premiere, but who exactly is he?

Related: Demon Slayer's Upper Rank demons explained: Who are the Kizuki?

Who is Yoriichi Tsugikuni?

Yoriichi Tsugikuni is a Demon Slayer from 300 years ago, and the inspiration for Kotetsu’s training doll. We won't spoil too many specifics about his story and relationships below, but here are a few key facts to know.

The short version is that Tsugikuni is widely regarded as the strongest Demon Slayer in the franchise’s fiction and was the inventor of the ‘breathing styles’ that the Demon Slayer Corps use. He also possessed a number of special, supernatural abilities that are unique to only the very top Hashira (plus a few people you might know).

Being the inventor of Breathing Styles, he was also responsible for the Sun Breathing technique, aka Hinokami Kagura, that Tanjiro’s family honed.

This isn’t his only connection to our hero though, as you might have guessed by his Hanfuda earrings. In fact, Tsugikuni was close friends and traveling companions with Tanjiro’s ancestor Sumiyoshi, and it was Sumiyoshi’s dream (or memory) that we briefly glimpsed in episode one.

The last thing to know about Tsugikuni is that it’s not a coincidence that he looks so similar to the top-ranked Upper Demon, Kokushibo.

The pair were brothers before the latter’s transformation, but we won't spoil how that went down as we’re sure the anime is going to do a hell of a job adapting it.

What is the Yoriichi Type Zero sword?

As a Demon Slayer, Yoriichi Tsugikuni carried a fairly standard Nichirin katana — deep black in color, that changed bright red during combat. This is the sword that appeared out of the neck of the doll at the end of Demon Slayer season three’s second episode.

In the manga Tanjiro has the sword repaired by Haganezuka, who he initially traveled to the Swordsmith Village to find.

Demon Slayer seasons 1-2 are available on Netflix, with new episodes of season 3 airing every Sunday on Crunchyroll.