The production team for That Time I Got Reincarnated as a Slime has confirmed that the anime’s third season will premiere in Spring 2024. In addition, several projects are planned to celebrate the 10th anniversary of the series’ web novel serialization on Shousetsuka ni Narou on February 20, 2013. 

The first project is a 3-part OVA adaptation of Coleus’ Dream — a side story from the main series. The OVA will premiere sometime in Fall 2023 and more details about its release will be announced soon. It is important to note that Coleus’ Dream is an unconfirmed English translation of the original Japanese title. 

The opening theme song for Coleus’ Dream will be performed by Takuma Terashima, who also played the role of Rimuru’s past form, Satoru Mikami. 

The story of Coleus’ Dream was initially written by series writer Fuse as the main concept of the That Time I Got Reincarnated as a Slime the Movie: Scarlet Bond film, taking place between the anime’s first and second seasons. Similar to that film, the OVA’s story will follow Rimuru fighting back against a conspiracy in a distant kingdom. It was originally included as a bonus booklet in one of the Blu-ray sets for the anime’s second season. 

Other initiatives for the 10th anniversary of That Time I Got Reincarnated as a Slime include a special campaign, commemorating the series selling over 40 million light novel copies, and its first large-scale event. Additionally, a stage adaptation of the series is also in production for a planned performance in August 2023. More details will be announced at a later date. 

The original light novels are written by Fuse and illustrated by Mitz Vah. It was first published by Micro Magazine on May 30, 2014 and has released 20 physical volumes as of September 2022. In addition to an anime series, the manga has also inspired several manga adaptations, light novel spinoffs, and video games. 

The Scarlet Bond anime film premiered in Japanese theaters on November 25, 2022 and in worldwide cinemas earlier this year. Crunchyroll screened the film in North American theaters and describes the synopsis as: 

A long-running conspiracy is swirling over a mysterious power known as “Queen” in Raja, a small country west of Tempest. When a slime who evolved into a Demon Lord named Rimuru Tempest crosses paths with Hiiro, a survivor of the Ogre race, an incredible adventure packed with new characters begins. The power of bonds will be put to the test!

Source: Comic Natalie, TenSura Official Japanese Anime Twitter