Pacify : quell the anger, agitation, or excitement of.Quarrel : a heated argument or disagreement, typically about a trivial issue and between people who are usually on good term.Challenge : a call to someone to participate in a competitive situation or fight to decide who is superior in terms of ability or strength.Threaten : state one's intention to take hostile action against (someone) in retribution for something done or not done.Darken : make or become dark or darker.Antonym of Pacify is Quarrel