That Time I Got Reincarnated as a Slime Season 4｜April 2026 Release with Epic 5-Cour Project

On December 19, 2025, the long-awaited major news for global anime fans was officially unveiled! During the official "TV Anime 'That Time I Got Reincarnated as a Slime' Season 4 Major Announcement Livestream," information about the sequel to this super-popular isekai anime was announced.

This is not just a renewal announcement but an unprecedented large-scale production project. This article compiles the broadcast time for 'That Time I Got Reincarnated as a Slime' Season 4, its astonishing episode count scale, and the new antagonists and core plot that will appear.

Season 4 Will Be Presented in a Grand "Full 5 Cours" Format

According to the latest special video released by the official source, 'That Time I Got Reincarnated as a Slime Season 4' is confirmed to officially begin airing in April 2026.

What shocked fans the most is the production scale this time. Unlike the previous half-year series format, the official announcement states that Season 4 will be a super-large-scale project consisting of "a full 5 cours":

• Initial Broadcast Schedule: Starting from April 2026, the first 2 cours (half a year) will be broadcast consecutively.
• Subsequent Plan: The remaining cours are expected to be released gradually in a split-cour format.

In this brand new special video produced by animation studio 8bit, Rimuru's best partner—the Great Sage—personally announced this news, and Rimuru's surprised expression has also become a hot topic among fans.

Season 4 Plot Preview: The Conspiracy of the Russel Clan and the Awakening of a New Hero

As the Monster Federation successfully holds its Founding Festival and establishes diplomatic relations with various countries, Rimuru is dedicated to realizing a "Human-Monster Co-prosperity Sphere" where humans and monsters coexist. However, behind this prosperity lies deeper shadows. The core conflict of Season 4 will revolve around the confrontation between Rimuru and the masterminds behind the Western Nations.

The Threat of the Kingdom of Hiruterozo

The plot focus will shift to the "Five Elders" of the Kingdom of Hiruterozo. Among them, the head of the Five Elders and a former hero, Kuranberu Russel, and his granddaughter Mariabell Russel, will become the main antagonists of this season.