5) Heimdall
While not the most significant character on this list, Heimdall’s death could have a big impact on Avengers: Infinity War. We know that the Asgardian is a formidable and wise figure, so if Thanos were to cut him down it would certainly prove just how dangerous he is.
We’re imagining that Thanos could lay siege to Asgard in order to retrieve an Infinity Stone that’s kept there, which is when he kills Heimdall. To avenge his death, Thor returns to Earth and teams up with the rest of the heroes to stop the villain. Sounds probable, right?
Idris Elba has previously vocalized his dismay at being tied down to the MCU, so it would probably be best if the actor was let go from his contract soon. And, it would be great if the Gatekeeper of the Bifrost could go out in a shocking, tragic death, rather than just disappearing from the franchise like other characters have done.