Avengers: Endgame - 13 Best Callbacks To The MCU

13. The Cave

The fact that Tony Stark's arc in the film begins with him stranded in space with low resources, little-to-no chance of survival, while wearing a tank top through which we can see his arc reactor is a direct callback to the beginning of his first ever arc in the MCU: when he was in the cave in the very first Iron Man.

There, Tony was held hostage by terrorists in a cave and had to escape using only his brains and cunning. In doing so, he builds his first ever Iron Man suit and escapes successfully. He does so with the help of his one and only friend in the cave, Ho Yinsen.

In Endgame, things are a little more complicated. Nebula more-than-fills the Ho Yinsen role as Tony's only assistance, but even when they put their brains together they remain unable to find a solution, merely prolonging their lives rather than saving themselves.

It's a fun callback and subsequent subversion when Tony and Nebula are ultimately saved thanks to the combined efforts of Captain Marvel and Pepper Potts.