Create a photorealistic image of an Ultramarine space marine in full, detailed power armor, featuring the distinctive blue and gold color scheme and the Ultramarine chapter emblem on the shoulder pads. The marine is in the middle of a battle, firing a heavy bolter with both hands. His head is replaced by the character Eustace Bagge from Courage the Cowardly Dog, with his classic annoyed expression, glasses, and small brown hat. The marine is yelling fiercely as he shoots, and the scene is set in a chaotic battlefield with explosions and gunfire in the background