Nightmare

Nightmare (悪夢) is the first chapter of the spin-off manga adaptation of That Time I Got Reincarnated as a Slime, Clayman's Revenge.

Summary
As Clayman is being engulfed by Rimuru's Beelzebuth, he desperately begs for his mentor, the former Demon Lord Kazalim's help but is ultimately engulfed alongside his Soul. However, this scenario turns out to be a nightmare as a sleeping Clayman awakens and laughs at seeing such a nightmare. He then heads to meet Laplace who greets him and suspects he had a hangover. Suggesting him not to drink too much, Laplace is surprised to see Clayman in this state and asks whether was he feeling ill (which was quite rare). Laplace later informs Clayman about Koenig, who initially forgets about him, but later remembers about the Majin and reveals that he went to Leon's territory to deal with him. Clayman doubts his victory and states that he will take revenge from Leon, while remembering about Kazalim's conversation with him related to his ascension as a Demon Lord.

Laplace hits Clayman on the head, stating that when it comes to Leon, he would be blinded by his desire for vengeance and reminds him about Tear and Footman's words. He states that there is no reason for being hasty in their plans and that they should execute them at ease while asking Clayman to put more trust in his friends. Clayman agrees and states that Laplace had seemingly given him valuable advice in his dream as well, to which the Wonder Pierrot states he should listen to his friend's advice and asks him about what kind of nightmare did he see. Clayman embarrassingly reveals it was a dream where a Slime killed him decades later, to which Laplace bursts in laughter.

Following Laplace's advice, Clayman begins preparations for the Orc Disaster plan, and several decades later he meets "that Lord" and forges an alliance with him, increasing the Moderate Harlequin Alliance's strength. During the Orc Disaster incident, Laplace shows Clayman the events going on, including Rimuru's presence that sends chills down his spine. After the failure of the Orc Disaster plan, Clayman keeps an eye on Rimuru, and through the Moderate Harlequin Alliance, brings in the Charybdis to attack Tempest.

Trivia

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