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Intro. .Rimuru Tempest's evolution to Demon King was triggered in a moment of desperation in which he had to sacrifice souls to save his people. After witnessing an army attack on the orcs and his friend Shizue's village, Rimuru is forced to absorb the souls of his enemies to evolve and save the survivors of his allies. This grants him unprecedented power, cementing him as one of the most powerful and unique Demon Lords to have evolved as a Great Demon Lord. Rimuru Tempest's story as an Awakened Demon King is marked by key events that transformed his power and status in the world of Tensei Shitara Slime Datta Ken. Its evolution was a unique process, culminating in the " Harvest Festival.

Rimuru Tempest Demon Lord

@Juan