The Orc War arc in That Time I Got Reincarnated as a Slime is one of the series’ best and most significant story arcs. Prior to this, the focus of the story was mainly on Rimuru and the goblin village. However, when the Ogres arrive, driven from their homes by an overwhelming army of Orcs, Rimuru is faced with a major challenge and has to seek allies and make agreements with nearby groups. This not only leads to an exciting war arc but also introduces many characters who become staples of the series.
The Orc War introduces characters like Shuna, Shion, Gabiru, Geld, and the other Ogres, who play key roles in Rimuru’s journey. It also introduces the Demon Lords, who become major players later in the series, and sets the stage for Rimuru’s own rise to power. The aftermath of the war results in the Orcs being absorbed into Rimuru’s village, significantly increasing its population and establishing it as a major political force in the region. This leads to the founding of the Jura Forest Alliance and further expands the scope of the story.
The Orcs pose a threat that Rimuru cannot solve alone, leading them to seek out allies to prevent their destruction. Rimuru’s ability to turn enemies into friends is showcased in this arc, as they first ally with the Ogres and eventually win over the entire Orc army. Instead of slaughtering the Orcs after defeating their leader, Rimuru chooses to include them, recognizing their humanity and treating them as equals.
The Orc War marks a turning point for the series, as it expands the story’s scope and introduces political elements that were not previously relevant in the small village setting. Many of the developments in this arc have significant ramifications and are revisited later in the series. Additionally, it introduces beloved characters that fans grow attached to. While the series has other high points after the Orc War, it never quite surpasses the impact and quality of this arc. However, with the announcement of Slime season 3, it remains to be seen if the upcoming season can surpass the high watermark set by the Orc War arc.