Mark Ruffalo on what Hulk is really afraid of and how that impacts ‘Avengers 4’

For ten years in the Marvel Cinematic Universe, Hulk was allowed to believe he was “The strongest one there is.” Then Thanos showed up, put a beating on the Hulk, and the Green Goliath hasn’t come out since. This had many assuming Hulk fears The Mad Titan, but there is another who scares the Hulk even more.

Avengers: Infinity War directors Joe and Anthony Russo have previously clarified that fear of Thanos was not the reason Hulk refused to show up again after the film’s first scene. Instead, Hulk was simply tired of only being called upon to clean up Banner’s mess.

Hulk had his own life for two years from Avengers: Age of Ultron to Thor: Ragnarok. He had a nice place to live and all the glory and admiration he could crave as the Grandmaster’s champion on Sakaar. The idea of going back to being a big, green lifeguard on part-time duty is understandably unappealing and it actually points to the one person who scares Hulk more than Thanos ever could, even with all six Infinity Stones.