There have been quite a few MCU movies that aren’t necessarily required viewing in order to understand their over-arching plots, such as Iron Man 2, Iron Man 3, Ant-Man, Black Widow, Thor: The Dark World, and The Incredible Hulk.
While the most pivotal MCU films contain bigger villains (like Thanos and Loki) and plots revolving around the infinity stones, the least essential MCU films are more personal stories involving the main heroes, and how they have to resolve conflicts that question their
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