Demonic teal warhorse rearing in a stormy cavern

A monstrous, muscular, dark teal horse with a long, flowing tan mane and tail is depicted rearing up, its front hooves lifted. It has sharp, demonic teeth bared in a snarl, piercing red eyes, and two curved, pointed horns on its head. The creature stands in the center-right of the frame, facing towards the left with its body turned slightly. A human arm, adorned with gold bracers, is reaching out towards the horse's head from the right edge of the image, while a human foot in ornate golden leggings is visible at the bottom right. The setting is a rough, rocky cave or grotto with water splashing dynamically around the creature's legs. The lighting is dramatic and moody, with deep shadows and highlights that emphasize the creature's physique. Rain streaks across the dark, atmospheric background. The perspective is low and close to the ground, enhancing the imposing and fearsome presence of the creature. The overall style is dark fantasy, with a powerful, epic, and slightly terrifying atmosphere.