What are some common methods villains use to infiltrate the Avengers?

Villains use various strategies to infiltrate the Avengers, including posing as allies, exploiting vulnerabilities in the team's defenses, and using deception and manipulation. They often impersonate heroes or gain access to secure locations through trickery or bribery. Some villains are even able to shapeshift or mimic appearances, making detection difficult. Understanding their weaknesses and maintaining vigilance are crucial to the Avengers' survival.