Heresy-era Arthurian Space Marine in Knightly Black Armor

A photorealistic depiction of a Heresy-era Arthurian space marine wearing ornate knightly black power armor with gold inlays and heraldic skull emblems. Set amid industrial steam, pipes and machinery, the scene emphasizes a heavy, solemn mood, detailed metallic textures and battle-worn insignia, fusing medieval chivalry with grimdark sci-fi realism.