Berluse
Berluse, an Arthurian knight who confronts King Mark as a traitor and is left wounded, attested in 1 source.
Berluse appears in Le Morte d'Arthur in a single chapter devoted to his confrontation with King Mark. Upon seeing Mark, Berluse calls out: "Traitor, keep thee from me for wit thou well that I am Berluse" (Le Morte d'Arthur, Book X, Chapter X). When Sir Dinadan takes Mark's part, Berluse expresses regret but resolves to fight: "Well, Dinadan, said Sir Berluse, me repenteth that ye will take part with him, but now do your best" (Le Morte d'Arthur, Book X, Chapter X). The encounter ends badly for Berluse: "they took their horses and departed and left Sir Berluse there sore wounded" (Le Morte d'Arthur, Book X, Chapter X).
All three citations come from a single chapter. Berluse's hostility toward Mark is declared openly and without preamble -- he addresses the king as "Traitor" before any combat begins. The scene illustrates the pattern of enmity that surrounds Mark throughout the Tristram sections of the Morte; Berluse is one of several knights who confront Mark for his treachery. His wounding and abandonment on the field underscores the cost of opposing a king, even a treacherous one, without sufficient allies.
Appears in: Beings, Entities in Le Morte d'Arthur, British Tradition