Also for the record your argument that gunfire echoing throughout the cave would somehow give your character greater clarity of vision is laughable at best. Animals that use echo-location above the surface of the water, bats, have exceedingly sensitive hearing and would be running away in fear and generally disorientated by something as loud as a chain-gun blasting away a few feet from its head. I'm sure you're ignoring all the limitations of your character's echolocation, but I'd appreciate it if you didn't bullshit science advantages that don't exist.