A brand-new trailer has been released for That Time I Got Reincarnated as a Slime Season 4, and fans are finally getting a closer look at what is coming next. The preview also gives a first listen to the opening theme song “Esoragoto” performed by Eir Aoi, known for her powerful anime songs. Along with the trailer, a colorful key visual has been shared ahead of the April 3 premiere in Japan.
The new video shows that Rimuru Tempest’s journey as a Demon Lord is about to face even bigger challenges. After building the Jura Tempest Federation into a peaceful nation where humans and monsters can live together, Rimuru now wants to create a stronger alliance between different races. His dream is simple — a world where everyone can live in harmony. But making that dream real will not be easy.
The trailer quickly shows that new political conflicts are rising. Granville Rozzo and his granddaughter Maribel Rozzo appear ready to oppose Rimuru’s growing influence. They believe that ruling over humanity is the only way to protect it. This creates a direct clash of ideas. Rimuru wants cooperation and equality, while the Rozzo family believes in control and power.
At the same time, another Demon Lord, Leon Cromwell, is quietly working toward his own mysterious goals. The trailer hints that Leon’s actions could affect the balance of power. His calm but serious expression suggests that something important is about to happen in the world.
One of the most exciting moments in the preview is the mention of a new Hero awakening. Heroes in this series are powerful beings chosen to fight against Demon Lords. The idea that a new Hero is about to appear adds tension to the story. Will this Hero become Rimuru’s enemy, or could they become an ally? The trailer does not reveal the answer, but it clearly shows that the world is changing again.
The animation looks bright and smooth, with large battle scenes and emotional close-ups. Studio eightbit returns to handle the production. Naokatsu Tsuda directs the season, supported by Kenji Yasuda and Atsushi Nakayama. The character designs by Ryoma Ebata remain colorful and expressive, keeping the familiar look fans love.
The opening theme “Esoragoto” by Eir Aoi plays during the trailer, giving it an energetic and emotional feeling. The song builds excitement for the new season. It mixes strong vocals with fast beats, matching the action shown on screen. Meanwhile, the ending theme “Katsubo” will be performed by CiON, adding another fresh sound to the series.
Another big announcement is that Season 4 will be split into five cours, with the first two airing one after the other. This means fans can expect a long and detailed story arc. The extended format suggests that the upcoming conflicts will take time to develop fully.
The trailer also reminds viewers that Rimuru is no longer just a friendly slime. He is now a true Demon Lord with massive responsibility. As Tempest grows stronger, other nations begin to worry. Some fear him, some respect him, and some want to challenge him.
The newly released key visual shows Rimuru standing confidently among his allies. Familiar characters like Benimaru, Shion, and other Tempest leaders appear ready for action. Their determined expressions suggest that they will stand by Rimuru no matter what happens.
In addition to the TV season, the franchise continues to expand. The second anime film, That Time I Got Reincarnated as a Slime the Movie: Tears of the Azure Sea, recently opened in Japanese theaters and will be released worldwide soon. This shows how popular the series has become around the world.
Season 4 promises bigger battles, deeper political struggles, and emotional turning points. Rimuru’s peaceful dream is getting closer to reality, but powerful enemies are rising. The awakening of a Hero, the schemes of Demon Lords, and the ambitions of human leaders all point to one thing — the world is about to change again.
With strong music, beautiful animation, and high stakes, the new season looks ready to deliver another exciting chapter in Rimuru’s adventure.