The Sapphire Khezu is a mutation, it has grown the muscles in excesive amounts, the blue coloration is due to blood circulation issues, due to the body hardly being able to contain the muscle tissue, the bones and organs get compressed against each other, for this reason the Sapphire Khezu endures a constant pain. It is known for the crying noises it makes due to this pain, it will attack anything that it can detect without a warning, usualy moving in erratic patterns and releasing electricity much more frequently than the Red or White Khezu.