If you're specifically looking for a 2021 release related to "Arn: The Knight Templar," it might be a sequel or related content that was produced later. The sequel, "Arn: The Kingdom at Road's End" (Swedish: "Arn - Riket vid vägens slut"), was released in 2008. For any newer content directly related to the character or story, you might need to look into other adaptations or related news.

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