Mysterious monsters appear as Naofumi is preparing for the next Wave. At the same time they show up, the Wave countdown stops. The Queen summons the Four Cardinal Heroes, and tells them that the Spirit Tortoise has revived.

The leaders of all the nations’ militaries gather in the Spirit Tortoise Kingdom. Naofumi is there as well, and promises to offer his help as one of the heroes. But just before they decide on a plan, a mysterious woman appears…

The Spirit Tortoise begins its march once more, appearing at the border of the kingdom bearing its name. Naofumi volunteers to lure away its familiars while the army tries to bring it to the mountains. The Spirit Tortoise’s familiar, Ost, fights alongside the humans…

The Spirit Tortoise’s head was cut off, but Ost, its familiar, is still alive. It could revive at any moment. The allied armies need to get back into fighting shape, and fast. Naofumi makes the risky move of heading onto the Tortoise’s back with only a small group, and tries to find its true weak spot.

Naofumi is met by L’Arc, Glass, and Therese. They’re after the person who broke the Spirit Tortoise’s seal and is controlling it. L’Arc proposes teaming up again…

Fitoria appears when the Spirit Tortoise revives, and with her help, Naofumi attempts to destroy its heart and cut off its head at the same time. L’Arc arrives as well, but all of them are helpless before Kyo’s overwhelming power.

Naofumi wakes up in a strange prison to find him and his party at level 1, and Filo missing. They start to raise their levels in order to escape, but things quickly turn against them when a dangerous monster suddenly appears…

Naofumi’s party heads for the Dragon Hourglass of Mikakage, in order to get to Sikul, the country that summoned Kizuna. Along the way, he sells rare healing items to make a hefty profit. He hears a rumor about a genius mage…

Naofumis party is teleported to Sikul, where Kizuna introduces the Vassal Weapon Hero, Ethnobalt. He soys he can use a piece of Raphtalia's hair and Naofumis blood as a catalyst that can create a shikigami to find her. He creates the shikigami, and they find.

Raphtalia is imprisoned in a Raybul Kingdom prison. She’s wary of L’Arc’s team, who is also imprisoned there, but asks them for help in escaping. Glass is weakened by the draining power of the prison. Raphtalia has a plan to escape, but…

Naofumi's party is overjoyed to be reunited with Raphtalia. Kizuna criticizes Glass for invading another world. Glass and L'Arc swear they won't fight Naofumi anymore, and instead find another way to solve their problem. Meanwhile, Kyo's plot proceeds.

The Wave appears before its scheduled time. Kizuna's group is teleported to it while Naofumi and his party head for Kyo's lab on Ethnobalt's ship. There, they see the true depths of Kyo's wickedness...

Raphtalia recalls having to buy clothing for her smaller self. Kizuna remembers being alone for so long. Rishia remembers Ost trying to give advice.

Seeking to reunite the scattered inhabitants of Lurolona Village who were sold into slavery, the Shield Hero and his party head to Zeltoble to secretly compete in the underground fights at the coliseum.

Naofumi's party enters the underground arena while concealing their identity. As they win and rise through the ranks, they're forced to confront the greed and lawlessness that lurks both without and within the arena. And when the final battle arrives, Raphtalia recognizes her opponent…

Naofumi visits the slave market, where the demi-human slave Fohl asks him to save his sick sister. Naofumi asks him if he's prepared to pay the price, but… Meanwhile, Lurolona Village is beginning to come back to life as the rescued demi-humans return, but a grave danger awaits it.

The Spear Hero, Motoyasu, has been sighted, and Mirelia asks Naofumi to persuade him to return. Naofumi is about to leave his lands to Eclair and go look for Motoyasu when an unexpected visitor arrives. And they also meet someone unexpected in the town where Motoyasu is staying…

Naofumi's party is attacked by a pair of mysterious and powerful men. S'yne arrives during the battle and finally attempts to explain why she wants to become one of Naofumi's followers. Meanwhile, more villagers are training in Hengen Muso.

Ren is haunted by the deaths of his party members in a failed attempt to defeat the Spirit Tortoise, and doesn't want to believe that he might be responsible for what happened. Myne seems ready to take his side and support him, but...

Keel and other demi-human children in the village are starting to learn how to assume therianthrope form like Sadeena. Ren is now staying in the village while suffering the effects of the Curse swords, and doing his best to fit in.

Naofumi assembles a party to pursue Gaelion, who has consumed the Emperor Dragon's Core. Gaelion's transformation is profoundly sickening Filo, so Naofumi must return Gaelion to normal within the next two days.

Naofumi's party regroups and plans another assault on the Emperor Dragon. While their plan of attack comes together, Wyndia explains her connection to the dragon. This causes Wyndia to remember something very significant...

Filo has recovered but needs to gain experience to replace her lost levels. S'yne returns from the underground arena bearing a tale of a suspiciously familiar new fighter who uses a bow and goes by the alias Perfect Hidden Justice.

Rishia faces Itsuki in the underground arena. As Itsuki rants and raves, it's clear that he's also come under the mental influence of Myne and unlocked a Curse series. Naofumi evacuates the children as Rishia enters her most dangerous fight yet.

Naofumi begins training in the Way of the Dragon Vein with Sadeena and Gaelion. Back at the village, the blacksmith visits, bringing new equipment for Raphtalia. When she tries it on, it reveals a shocking secret about her past...