For the longest time, the death of really big heroes wasn't a thing in the Marvel Cinematic Universe. Granted, fans witnessed how characters like Vision, Groot, and Phil Coulson bit the dust in a specific project, but they all eventually returned one way or another. Quicksilver was one of the unlucky few who really stayed out of the picture for many years without any plans for a potential revival. However, all of that changed the day Avengers: Endgame premiered.

Earth's Mightiest Heroes' latest adventure acted as the perfect farewell for fan-favorites such as Iron Man, Black Widow, and Steve Rogers' Captain America. Since that day, audiences learned that no one is truly safe in the MCU anymore, which will especially hold true the closer we get to the end of the Multiverse Saga. Avengers: Doomsday and Avengers: Secret Wars will undoubtedly mark the final appearances of many big characters,...