That Time I Got Reincarnated as a Slime

A New World Built on Friendship and Power

That Time I Got Reincarnated as a Slime is one of the most popular modern isekai anime, blending fantasy, action, comedy, and kingdom-building into a story about creating a better world. Based on the light novel series by Fuse and illustrated by Mitz Vah, the anime follows an ordinary man who is reborn in another world as a seemingly weak slime monster.

Rather than pursuing conquest through fear, the protagonist Rimuru Tempest uses diplomacy, intelligence, and overwhelming power to unite monsters, humans, and other races under a single nation. As his influence grows, so do the challenges facing his kingdom.

The series is known for its expansive world-building, memorable cast, large-scale battles, and gradual transformation from a simple adventure into an epic fantasy about politics, alliances, and survival.

Series Overview

Title: That Time I Got Reincarnated as a Slime
Japanese Title: 転生したらスライムだった件 (Tensei Shitara Slime Datta Ken)
Seasons: 4 Seasons
Episodes: 72 Episodes
Air Date: October 2, 2018 – March 19, 2019
Studio: 8bit
Streaming Platforms: Crunchyroll, Netflix (availability varies by region), Amazon Prime Video, Blu-ray, DVD
Opening Themes: "Nameless Story" by Takuma Terashima, "Megurumono" by Takuma Terashima, "Storyteller" by Miho Karasawa, "Like Flames" by MindaRyn, "Peacekeeper" by STEREO DIVE FOUNDATION
Ending Themes: "Another Colony" by Miho Karasawa, "Little Soldier" by Azusa Tadokoro, "STORYSEEKER" by STEREO DIVE FOUNDATION, "Reincarnate" by Takuma Terashima, "Believer" by Rin Kurusu

Story Summary

Satoru Mikami is an ordinary office worker whose life ends unexpectedly after a random attack. Instead of dying, he awakens in a fantasy world as a slime—a creature usually considered one of the weakest monsters imaginable.

However, his new body comes with extraordinary abilities that allow him to absorb skills, analyze objects, and grow stronger through every encounter. After meeting the legendary Storm Dragon Veldora, he receives the name Rimuru Tempest and begins exploring his new world.

As Rimuru travels across the Jura Forest, he forms friendships with goblins, direwolves, dwarves, ogres, lizardmen, and many other races. Rather than ruling through fear, he chooses cooperation and diplomacy, gradually creating the Jura Tempest Federation, a nation where monsters can live in peace and prosperity.

As Tempest grows, it attracts the attention of powerful kingdoms, demon lords, religious organizations, and ancient threats. Rimuru's dream of peaceful coexistence is repeatedly challenged by war, political intrigue, and the harsh realities of leadership.

Through victories, tragedies, and personal growth, Rimuru evolves from a simple slime into one of the most powerful and respected figures in the world.

Season Breakdown

Season 1 (2018–2019) — The Birth of Tempest

Season 1 introduces Rimuru Tempest and the fantasy world he now calls home. As he forms alliances with goblins, wolves, lizardmen, and other races, the foundations of the Jura Tempest Federation begin to take shape.

The season focuses on world-building, nation-building, and major threats such as the Orc Lord and Charybdis.

Season 2 (2021) — The Rise of a Demon Lord

Season 2 dramatically raises the stakes as Tempest comes under attack. The devastating conflict forces Rimuru to make difficult choices that permanently change both himself and his nation.

The season culminates in Rimuru's evolution into a Demon Lord while tensions between humans, monsters, and other Demon Lords continue to escalate.

Season 3 (2024) — Diplomacy and New Alliances

Season 3 centers on the Holy Empire of Lubelius conflict and Rimuru's growing role among the world's major powers.

With Tempest's influence expanding, diplomacy, political negotiations, and relations with the Council of Demon Lords become just as important as battlefield victories.

Season 4 (2026–2027) — Expansion of the Federation

Season 4 follows Rimuru's continued efforts to expand and strengthen the Jura Tempest Federation. As Tempest grows into a major world power, new internal disputes, political challenges, and economic conflicts emerge.

Adapted from some of the light novel's most detailed world-building arcs, the season is scheduled as a long-running multi-part broadcast beginning in April 2026.

Movie Breakdown

That Time I Got Reincarnated as a Slime: The Movie – Scarlet Bond (2022)

Set after Season 2, Scarlet Bond follows Rimuru as he becomes involved in a conspiracy surrounding the kingdom of Raja. Featuring an original story supervised by series creator Fuse, the film expands the world beyond Tempest while introducing new allies, enemies, and political intrigue.

That Time I Got Reincarnated as a Slime: The Movie – Tears of the Azure Sea (2026)

Premiering in February 2026, Tears of the Azure Sea takes place immediately after Season 3. Rimuru and his companions travel to a resort island, where a new adventure unfolds while setting up events that lead directly into Season 4.

Spin-Offs & Side Stories

The Slime Diaries (2021)

A slice-of-life spin-off based on Tensura Nikki. Set between Season 1 and Season 2, the series focuses on everyday life within the Jura Tempest Federation.

Rather than major battles or political conflicts, the story highlights festivals, friendships, seasonal events, and the daily interactions of Tempest's residents, with Rimuru acting more as a caring community leader than a warrior.

That Time I Got Reincarnated Again as a Workaholic Slime

A non-canon parody spin-off that places Rimuru in a modern office setting. This alternate-universe comedy focuses on workplace culture, endless paperwork, office politics, and the challenges of corporate life.

Major Story Arcs

• Jura Forest Arc — Rimuru begins his new life, forms alliances with monster races, and establishes the foundations of Tempest.

• Orc Lord Arc — Rimuru faces the growing threat of the Orc Lord while bringing multiple races together under a common cause.

• Charybdis Arc — Tempest confronts the massive calamity-class monster Charybdis alongside powerful allies.

• Falmuth Invasion Arc — A devastating attack on Tempest changes Rimuru's outlook and sets the stage for a major transformation.

• Demon Lord Awakening Arc — Rimuru evolves into a True Demon Lord and reshapes the balance of power across the world.

• Walpurgis Arc — The Demon Lords gather as Rimuru confronts Clayman and claims his place among the world's strongest rulers.

• Holy Empire of Lubelius Arc — Tempest's relationship with the Western Holy Church and Lubelius becomes a major focus.

• Council of Demon Lords Arc — Political negotiations, diplomacy, and shifting alliances redefine the future of the continent.

• Tempest Expansion Arc — Rimuru's nation continues to grow in influence through trade, diplomacy, and international cooperation.

• Economic and Internal Conflict Arc — As Tempest becomes a global power, political and economic challenges begin emerging from within and beyond its borders.

Main Characters

• Rimuru Tempest — The founder of Tempest and one of the world's most powerful beings.

• Veldora Tempest — The legendary Storm Dragon and Rimuru's closest friend.

• Benimaru — A powerful commander who leads Tempest's military forces.

• Shuna — A skilled diplomat and administrator within the federation.

• Shion — Rimuru's loyal secretary and formidable warrior.

• Milim Nava — One of the strongest Demon Lords in existence.

Themes & Tone

• Nation Building — Creating a prosperous society is at the heart of the story.

• Friendship and Unity — Cooperation allows different races to thrive together.

• Leadership and Responsibility — Rimuru must balance power with compassion.

• Politics and Diplomacy — Alliances often shape the future more than battles.

The series blends fantasy adventure, comedy, action, and political drama.

Animation & Audio

Studio 8bit brings the world of Tempest to life through vibrant visuals, large-scale battles, and detailed fantasy environments.

The series balances spectacular action sequences with quieter moments of world-building and character development, helping the setting feel alive and constantly evolving.

Its soundtrack and theme songs complement both the lighthearted and dramatic aspects of Rimuru's journey.

Where to Watch

You can watch That Time I Got Reincarnated as a Slime on:

• Crunchyroll
• Netflix (availability varies by region)
• Amazon Prime Video
• Blu-ray
• DVD

Similar Anime

• Overlord — A powerful ruler builds influence in a fantasy world.

• Tsukimichi: Moonlit Fantasy — A fantasy adventure centered around creating a thriving community.

• Log Horizon — Strategy, politics, and world-building take center stage.

• The Rising of the Shield Hero — A hero rises from adversity to protect those who rely on him.

• So I'm a Spider, So What? — Another monster-reincarnation story featuring growth and evolution.

Popularity & Reception

That Time I Got Reincarnated as a Slime has become one of the defining isekai franchises of the modern era.

Fans praise its world-building, engaging cast, political storytelling, and Rimuru's growth from an ordinary office worker into the leader of a thriving nation. The series consistently ranks among the most popular fantasy anime and has helped popularize kingdom-building stories within the isekai genre.

Final Thoughts

That Time I Got Reincarnated as a Slime has grown from a simple reincarnation story into one of anime's most successful fantasy franchises. What begins with an ordinary man awakening as a slime gradually evolves into an expansive tale of nation-building, diplomacy, warfare, and coexistence.

The series stands out within the isekai genre because it focuses not only on personal power but also on leadership and community. Rimuru's goal is never simply to become stronger than everyone else; it is to create a world where different races can live together without fear or prejudice. This emphasis on cooperation gives the story a unique identity among modern fantasy anime.

Across its multiple seasons, movies, and spin-offs, the franchise continually expands its world while maintaining a balance between action, humor, politics, and character development. Whether viewers enjoy large-scale battles, strategic negotiations, or lighthearted slice-of-life moments, there is something within the world of Tempest for every type of anime fan.

With Season 4 continuing Rimuru's journey and new stories still being adapted, That Time I Got Reincarnated as a Slime remains one of the most influential and enduring isekai series of the modern era. For newcomers and longtime fans alike, it offers a rich fantasy world filled with memorable characters, ambitious storytelling, and a vision of unity that continues to resonate throughout the franchise.