The spread of false information causes the Temple Knights to assemble, endangering Diablo's plan to conquer Falmuth. Meanwhile, Rimuru learns that Hinata is on her way to Tempest.

Expecting visitors from all races to come calling after learning that Rimuru now controls the entire Great Forest of Jura, Rimuru decides to hold a festival to introduce himself and Tempest to the world, with the goal of attracting new citizens.

It's day one of the festival, and Rimuru finally gets to see all of his friends' performances and presentations. As he's enojying the festivities, he's summoned by Luminus...

As prominent figures from several nations assemble in Tempest for a meeting, Laplace and his companions formulate a plan centered around Clayman. Then someone familiar joins the discussion...

Rimuru announces his plan to back Youm as the new king of Falmuth. After hearing this, Gazel tests Youm to see if he has what it takes to be a ruler, and Youm answers with full sincerity. Erald also takes a liking to Rimuru after hearing him say he just wants to create a world where everyone can prosper and smile. Thus Rimuru and his allies look ahead to the battle against their new enemy, Clayman.

After learning about an elf slave trade, Rimuru had Soei investigate, but it turns out the slave traders have already been shut down by Masayuki, the Lightspeed Hero. Word is now spreading that the Hero is headed to Tempest to slay a Demon Lord...

Gazel and Elmesia pledge to assist Rimuru with Tempest's lack of funding. Elmesia then proposes an alliance, but she's concerned about the danger Diablo poses.

Gabiru narrowly wins his battle against Hermes. Watching their outcome is Middray of the Dragon Faithful, whose skill was enough to overwhelm even Suphia. Though he looks like a human, he is actually a Dragonewt like Gabiru. Meanwhile, Yamza uses his artifact Doppelganger to create a double of himself, but Albis still defeats him soundly. He tries to surrender, but Clayman takes control of him and forces him to transform into Charybdis.

Responding to Rimuru's concerns about monsters in the forest harming humans, Vesta and Kaijin reveal a new invention they hope will keep the road to Tempest safe. Also, Rimuru assigns a new task to Geld.

After meeting with the kings of various nations, Rimuru heads to Engrassia to invite his former students to the festival. The kids are thrilled to go back with him to Tempest, but then the hero Masayuki arrives as well...

A martial arts tournament is being held! The winner will be given the right to challenge Rimuru. The hero, Masayuki, will be participating in the tournament. Rimuru wants to uncover the hero's true strength, so they get Geld and Gobta to participate.

Rimuru pays the merchants with the gold coins he's procured. The merchants try to garner futher favor, but Rimuru ceases trading with them. Rimuru then gathers his allies and calls for action again the eastern merchants who are operating in secret.

The slime Mikami and the Storm Dragon Veldora decide to give each other names. Veldora gives the slime Mikami the name "Rimuru," and Rimuru comes up with a family name for both of them: "Tempest." Then Rimuru uses his Predator skill to take Veldora into his body and analyze the "Unlimited Imprisonment" seal in hopes of breaking it... but this action sends a shock through the nations surrounding the Great Forest of Jura. With Veldora gone, there's a chance that the larger nations could become bold and invade the smaller provinces. With no knowledge of this, Rimuru leaves the cave and meets some Goblins.

After leaving the cave, Rimuru encounters a village of Goblins under attack by a clan of Direwolves. Caught in the heat of the moment, Rimuru agrees to help the Goblins in their battle. That night, the Direwolves arrive to try to take over as the new rulers of the Great Forest of Jura!

Rimuru and his companions visit the Dwarven Kingdom, the Armed Nation of Dwargon, in search of some artisans to help the Goblins learn to supply their own food, shelter, and clothing. However, a skirmish just outside the city gate lands Rimuru and Gobta in a prison cell. Then there's a report of an Armorsaurus in the nearby mines!

A new force has suddenly risen to power in the Great Forest of Jura, and its leader, Clayman, proposes that the Demon Lords hold Walpurgis with the goal of sanctioning the slime who deceived him. Rimuru also begins to prepare for a battle with Clayman, but observing the enemy army's movements reveals that Clayman's target is not Tempest, but Eurazania. Clayman's army will arrive in Eurazania within two days. Can Rimuru's forces get there in time?

To put a stop to Clayman's plans, Rimuru uses transport magic on a large scale to both move Tempest's army to Eurazania and evacuate the people of Eurazania to Tempest. Rimuru also decides to crash Walpurgis, the Demon Lords' banquet, in order to settle the score with Clayman personally. Since this will be a return match for Shion, he decides to take her and Ranga along. New military forces are organized in Tempest in preparation for the battle against Clayman's army. At last, the eve of battle is upon them...

The Seven Days Clergy have been purged, and the battle is over. Rimuru and Hinata hold a meeting to discuss future relations between their two nations, and the masterminds behind the whole conflict, the Eastern merchants, are revealed.

Everyone in Tempest is busy preparing for the festival to celebrate the country's opening. Rimuru visits Mjöllmile to share ideas on forms of entertainment that will keep people coming back for more.

Demon Lord Ramiris tries to argue her way into moving to Tempest, where there's great food, hot springs, and ample entertainment. Rimuru happens to walk into the argument and comes up with a way to make use of Ramiris's skills.

The night before the Opening Festival, Rimuru throws a lavish banquet for all the nobles and royalty visiting Tempest. When the party is in full swing, Empress Elmesia of the Sorcerous Dynasty of Thalion arrives, throwing everyone into chaos.

Benimaru leads his army to Eurazania, and Youm heads to Falmuth to take it over along with his buddies and Diablo. Rimuru succeeds in outwitting Clayman by transporting all of Eurazania's refugees to Tempest. Since Clayman has been striving to evolve into an Awakened Demon Lord for a long time, his resentment toward Rimuru grows. Meanwhile, Demon Lord Leon, Veldora's sister Velzard, and Guy, the oldest of the Demon Lords, become increasingly impressed with Rimuru.

Yuuki is saddened by the death of Clayman, and Luminus is saddened by the death of Roy. Steeped in sadness, and having lost their friends, they seek their next move against Rimuru, who has grown in power and become a true Demon Lord.

A war council led by Hinata is held in the Holy Empire of Lubelius. Moments after Hinata declares her intent to meet Rimuru and talk to him, she receives a hostile message from Rimuru.

Rimuru is building a dungeon in preparation for the upcoming festival. It will feature treasure chests containing weapons made by Kurobe, and Veldora will inhabit the deepest floor as the final boss. Then Milim suddenly shows up with a suggestion...