Universal foe is a term that refers to an entity that is universally disliked or opposed. Synonyms for this word include antagonist, nemesis, adversary, enemy, foe, opponent, rival, and challenger. These words all describe someone or something that is actively opposing or challenging others. An antagonist is a character or force that opposes the protagonist in a story. A nemesis is someone or something that brings about someone's downfall. An adversary is an enemy or opponent in a conflict. Enemy and foe are both used to describe someone who is opposed to someone else. Opponent, rival, and challenger all describe someone competing against someone else. These synonyms are all useful when describing a universal foe.