First Steps, the Russo brothers have teased its connection to their much-awaited MCU movie, Avengers: Doomsday. The directing duo recently took to social media to share a promotional post for the first entry in Phase Six of the MCU,

When Entertainment Weekly asked Fantastic Four: First Steps director Matt Shakman if Downey Jr. filmed that post-credits scene, the filmmaker pleaded the fifth. "For others to talk about," he teased. However, Shakman did reveal that it was the Russo brothers who helmed the post-credits scene since it was shot for Avengers: Doomsday.