archfiend

/ˌɑːrtʃˈfiːnd/
noun
  1. A very evil or cruel person; the most powerful or chief devil.
    • In the story, the archfiend rules over a dark kingdom of monsters.
    • The dictator was described as an archfiend by those who opposed him.
    • Legends often portray Satan as the archfiend who tempts humans.
Antonyms
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