Create a 4K digital painting of a robot wearing the bone crown in meat armor from the Warhammer universe. The robot should be dressed in a black trenchcoat with an open chest, showcasing its intricate, elegant, and highly detailed flesh ornate design. Set the scene in ancient catacombs with a smooth, sharp focus and an ethereal atmosphere. Incorporate elements of volleyball, as if the robot is engaged in a game. The style should be reminiscent of Artstation concept art, with influences from Greg Rutkowski and Alphonse Mucha. Output should be in the style of an Octane render