roaring knight
The overarching antagonist of Deltarune.
It is a living shadow that appears mainly as an androgynous humanoid (notably possessing a pair of antlers and stigmata-like holes in its hands resembling W.D. Gaster's) though it is capable of shapeshifting. It makes its first appearance as the final boss fight/Shadow Crystal bearer of Chapter 3, and acts as the main antagonist of Chapter 4 and onwards.
During the initial release cycle of the game, theories were abound on who the Roaring Knight was, with many claiming this or that character was the Knight.

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