Bound by Shadow: The Underworld Battle

Create an image depicting a teenage boy about 15-17 mounted on top of a great black bat (legs behind wings). The bats body should be roughly 10 feet long and his wingspan should be 20 feet. The boy should be bent over the bat with his left arm holding on tightly as the bat flies througu the air. In his right hand he should hold a simple longsword at the ready. The boy should be wearing black leather armour (nothing too fancy) and have a determined slightly tense expression. The bat should be flying directly towards a great white rat, which is roughly 12 feet tall. The rat should have white fur that is slightly iridescent and look have its claws at the ready facing the approaching bat and human ready to swing. The image should be extremely realistic high detail but fanstasy with a dark atmosphere set in the underworld with dark jagged rocks all around in a giant open cavern. Have the bat and rat follow real bat and rat anatomy as closely as possible while still being at the scale that they are.