That Time I Got Reincarnated as a Slime Season 4

That Time I Got Reincarnated as a Slime Season 4

Episodes

12 Aired

New Days

EP 01

2026.04.03 (金)·24分

New Days

新しい日々

The Founders Festival has ended in great success, and the Jura Tempest Federation takes a new step toward realizing the Human-Monster Prosperity Zone. While Rimuru Tempest is inspecting the town, he encounters adventurers arguing with Benimaru and the security team over conquering the Underground Labyrinth. After receiving complaints about the dungeon's difficulty, Rimuru Tempest gathers Veldora Tempest and others for an operational meeting. As Rimuru Tempest frets over the low level of the challengers, Masayuki proposes a game-like solution.

The Evolving Labyrinth

EP 02

2026.04.10 (金)·24分

The Evolving Labyrinth

進化する迷宮

Thanks to Masayuki's idea of opening rest areas and the publicity from the high prize money, the dungeon overhaul is a huge success! While Rimuru is relieved that management is on track, a party named "Team Green Rebellion," consisting of 100 members, arrives to conquer the dungeon. Furthermore, Hinata's training in the dungeon has caused the Floor Guardians from the 60th floor onwards to become non-functional. In response to this emergency, Rimuru sets out to strengthen the dungeon.

EP 03

2026.04.17 (金)·24分

Formation of the Avatar Team

仮魔体チーム結成

Rimuru and his friends have obtained avatars for the underground dungeon. However, with low-level avatars and uncoordinated combat styles, they are no match for Team Green Fury. Consequently, Rimuru begins special training with his companions.

Invitation

EP 04

2026.04.24 (金)·24分

Invitation

招待状

Even after repelling Team Gekiran, Rimuru and the others continued their special training in the underground labyrinth. Meanwhile, at the Council of the West in the Kingdom of Ingrassia, a certain discussion regarding the Jura Tempest Federation was being held.

The First Step

EP 05

2026.05.08 (金)·24分

The First Step

最初の一歩

Rimuru and his companions arrive in the Kingdom of Ingrassia following a summons from the Council of the West. When the Jura Tempest Federation requests to join the Council, the councilors present conditions driven by greed.

Council of the West

EP 06

2026.05.15 (金)·24分

Council of the West

西方諸国評議会

Rimuru is infuriated by the unreasonable demands from the Council. Furthermore, Prince Elrick of the Kingdom of Ingrassia appears, seeking to subjugate Demon Lord Rimuru, throwing the council into a volatile situation.

The Mastermind's True Identity

EP 07

2026.05.22 (金)·24分

The Mastermind's True Identity

黒幕の正体

Having successfully prevented the assassination of Elrick amidst the chaos, the council concludes safely with the Jura Tempest Federation joining. Upon returning to the Jura Tempest Federation, Rimuru and the others begin interrogating Glenda, the perpetrator of the assassination attempt.

Greed's Foothold

EP 08

2026.05.29 (金)·24分

Greed's Foothold

強欲の布石

Yuuki is controlled by Mariabell. Upon receiving information from Glenda, Rimuru decides to avoid interacting with the Free Association. However, the scheduled day for the ruins investigation with the Free Association was drawing near.

Ruins Investigation

EP 09

2026.06.05 (金)·24分

Ruins Investigation

遺跡調査

Rimuru and his companions arrive at the ancient ruins of Amrita. Although the group's investigation is proceeding smoothly, the ruins' defense mechanism suddenly activates and attacks the survey team. Furthermore, Mariabell makes an appearance...

The Master of Greed

EP 10

2026.06.12 (金)·24分

The Master of Greed

強欲の主人

Mariabell, who possesses the unique skill "Greed," and Rimuru, who has awakened as a Demon Lord. The difference in power between the two was obvious. Rimuru attempts to defeat Mariabell, but Yuuki stands in his way.

Milim's Friend

EP 11

2026.06.19 (金)·24分

Milim's Friend

ミリムの友達

Demon Lord Milim confronts the Chaos Dragon that she herself once sealed away. For the sake of Milim, who cannot bring herself to defeat her friend, Rimuru aims to protect the soul remaining inside the Chaos Dragon.

The Evolving Nation of Monsters

EP 12

2026.06.26 (金)·24分

The Evolving Nation of Monsters

「進化する魔国連邦」

With Mariabell's control broken, the Jura Tempest Federation has become the largest faction in the Council of the West. While facing a mountain of problems, Rimuru takes a breather by inspecting various locations, only to receive an urgent message from Ramiris.