A cinematic portrayal of a sinister merman emerges from the depths, his face twisted in a maniacal expression that hints at untold horrors. His humanoid features are contrasted by piercing, otherworldly yellow eyes that seem to glow with a malevolent energy against the pallor of his human-like skin. The scene is imbued with a melancholy quality, as dynamic lighting casts dramatic shadows across the ridges of his face, enhancing the eerie intensity of his gaze. The dark, unfathomable depths form a brooding backdrop, as if to suggest that this creature is a guardian of ancient secrets, lurking where light dares not enter. Subtle iridescent scales shimmer along his muscular arms, catching flecks of luminescence in the darkness, adding an ethereal dimension to his menacing allure.