המקרה בו חזרתי לחיים בתור רפש. That Time I Got Reincarnated as a Slime

It seems as if all is going smoothly, but Rimuru then receives a report that Milim has declared war and Eurazania has been destroyed, and there's still the matter of the Western Holy Church's hostility toward monsters, even with Falmuth out of the picture Tempest is preparing a feast in celebration of Rimuru's return home
The idea he comes up with is to have superior spirits inhabit each of them, as Shizu had, so their lives won't end prematurely That night, Rimuru has a dream in which he sees Shizu teaching children at her school in the Kingdom of Ingrassia—a dream showing Shizu's lingering regret

המקרה בו חזרתי לחיים בתור רפש: Season 1 (2018) — The Movie Database (TMDb)

But instead of a spirit, Chloe's summoning brings forth an unknown spiritual form with an immense amount of energy.

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That Time I Got Reincarnated as a Slime
המקרה בו חזרתי לחיים בתור רפש: Season 1 (2018) — The Movie Database (TMDb)
With no knowledge of this, Rimuru leaves the cave and meets some Goblins
That Time I Got Reincarnated as a Slime
The Orc army, led by the Orc Lord, continues its conquest throughout the Great Forest of Jura
Rimuru and the Class S students have made it through the first exercise of the Freedom Academy's annual outdoor training event Despite the initial conflict, Eurazania and Tempest have deemed each other to be worthy of establishing friendly relations, and diplomacy between them officially begins
Then there's a report of an Armorsaurus in the nearby mines! Soon after, the Lizardman Gabiru visits the village, having heard rumors about it But he's suddenly overcome by intense sleepiness at the same time, so he summons a demon to stop Razen, the one target who escaped alive

המקרה בו חזרתי לחיים בתור רפש: Season 2 (2021) — The Movie Database (TMDb)

Ramiris seems to sense something about it.

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המקרה בו חזרתי לחיים בתור רפש: Season 0 (2019) — The Movie Database (TMDb)
Upon arriving, she's surprised to see what a strong nation it is, but continues to talk with its citizens to learn more
Maybe
המקרה בו חזרתי לחיים בתור רפש: Season 1 (2018) — The Movie Database (TMDb)
The slime Mikami and the Storm Dragon Veldora decide to give each other names
לכל צופי אהבה זו מלחמה תדעו שהמתרגם ממשיך לעבוד במרץ אבל מכיוון ששוב אין לי אינטרנט אז נוציא אותם קצת באיחור המתרגם של ג'וג'ו שכולנו או רק אני? Rimuru's village has gained Benimaru and the other five Ogres as its newest allies Just what is this spiritual being? This story takes place before Rimuru's reincarnation
In it she finds surprising information about the Jura Tempest Federation, a nation of monsters The victim turns out to be Gabiru's younger sister, who reveals that Gabiru led an insurrection and left to fight the Orc Lord without waiting for the alliance

המקרה בו חזרתי לחיים בתור רפש: Season 0 (2019) — The Movie Database (TMDb)

They tell him that he can accomplish this using the power of Charybdis.

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That Time I Got Reincarnated as a Slime
Meanwhile, the Orcs begin to invade the marshlands surrounding Lake Siss that are inhabited by the Lizardmen
המקרה בו חזרתי לחיים בתור רפש: Season 2 (2021) — The Movie Database (TMDb)
Maybe
Shion and the rest of the fallen are revived, Diablo has joined the team