The crossword solution for the term 'Avengers Enemy' is Loki, a four-letter word. Loki is a character from Norse mythology who appears in Marvel's Avengers films as the main antagonist. He is the adopted brother of Thor and the son of Laufey, the ruler of the Frost Giants of Jotunheim. Loki is known for his mischievous and villainous behavior, often using his powers of illusion and manipulation to cause chaos and destruction.