Cat dominates over other cat, how to help?

This is perfectly natural behavior for cats. They should to be allowed to establish some level of dominance on their own. As long as neither of them are getting hurt, they and you will be better off in the long run if you just let it happen. Punishment never works in curbing aggression in cats. It simply makes the problem worse. Your cat may become fearful or turn its resentment toward you and the other cats. Instead, simply withdraw your affection as soon as an incident occurs. Its said that cats quickly learn that life suddenly got more boring after they became aggressive.