Complex sentence: His true form is that of a white giant monster with horns on the forehead that are capable of growing and retracting to be used as weapons, he's also capable of regenerating incredibly fast, rendering most injuries useless.
Split into simpler sentences: His true form is that of a white giant monster with horns on the forehead that are capable of growing and retracting to be used as weapons. He's also capable of regenerating incredibly fast, rendering most injuries useless.