Comic Book vs Film: How Avengers: Infinity War Is Already Different

12. Mephisto

In The Comics:

Thanos doesn't come to the fight alone. He's basically "advised" by Mephisto, who secretly harbours a desire to steal the Infinity Stones for himself to wield their power. He manipulates Thanos to try and get him into a position of weakness and eventually convinces him to limit his power to defeat his enemies as a means to prove himself to Mistress Death.

Unfortunately for Thanos, Mephisto then turns on him to try and steal the Gauntlet for himself.

In The Film:

As he hasn't yet been introduced into the MCU at all, there's no way we're going to see Mephisto involved in Infinity War. He's still a little bit too much of a supernatural character to really work with the way the franchise is currently. Why would Disney bring in the actual devil to a family-focused franchise, after all?