18 Most Heartbreaking Moments In The MCU (So Far)

The earliest of Marvel's more meaningful deaths, Ho Yinsen, whose role in saving Tony's life may have reshaped the entire universe, convinces Tony to fight for his own life, all the while ready to die.

Though he feeds Tony the idea that he ought to have something to fight for, teaching Tony to value what he has and the people in his life, he himself speaks of a family that's already died, pretending that he wants to go back to them so that Tony might find the same drive to live. With Tony fighting, at least, to ensure Yinsen's freedom, he's able to build the first iteration of the Iron Man suit, and with Yinsen's steady hands, create the first arc reactor to power the magnet in his chest.

In the end, however, Yinsen is shot by Ten Rings soldiers at the mouth of the cave, right on the cusp of freedom, revealing to Tony that he had no intention of living, wanting to see his family in death. The last message he imparts is one of the film's most memorable lines:

"Don't waste your life, Stark."

Clearly, "earth's greatest protector" has taken that to heart in the last decade.