Assault and Battery, the unlawful and willful use of force or violence on a person. They are separate offenses. An assault is a demonstration of an unlawful intent to injure another person. Actual physical contact need not occur. A battery is the unlawful touching or striking of a person, done with intent to do harm. Battery is always accompanied by assault, but assault can occur without battery. The offenses are felonies if a weapon is involved; otherwise, they are usually misdemeanors. They are also torts; the injured person may sue for damages.
What makes a person not only murder, but murder multiple people over days, weeks and even years? There's a special name for these types of murderers: serial killers.
With modern security, how can thieves walk out of a museum with millions of dollars worth of art? It usually just takes force and a little bravado.