Warning: This piece contains SPOILERS for Secret Invasion

Four years after Avengers: Endgame brought down the curtain on the first MCU Saga and permanently retired Iron Man and Captain America, Marvel has given us the lost post-credits scene audiences never got to see. Because of the heartbreaking death of Robert Downey Jr's Tony Stark and Cap's decision to stay in the past with Peggy Carter, Endgame bucked the MCU post-credits trend by having no stinger at all, other than an audio call-back to Iron Man's creation back in 2008. At the time, it was the right decision to give the movie's explosive events the space to breathe.

Had Marvel decided to tag on a tease for what comes next, Endgame's ending would have compromised the respectful portrayal of Tony Stark's death. Even with other movies already confirmed, explicitly reminding the audience that the show must go on, and that there's still money to be made would have been read as deeply cynical. As a result, Endgame is a rarity in the modern era - an MCU movie without a post-credits scene at all. But now, events in Marvel's Phase 5 confirm what actually happened immediately after the Battle of Earth while the Avengers buried Iron Man and watched Captain America head off for his happy ending.

Related: Every Marvel End-Credits Scenes Explained

Secret Invasion's Avengers DNA Twist Is Endgame's Missing Credits Scene

The shocking events of Secret Invasion episode 5's ending retrospectively reveal what happened on the Battle of Earth's battlefield after Thanos was defeated. Samuel L Jackson's Nick Fury admitted that he sent a squad of Skrull spies into the aftermath to "harvest" DNA left by the injured Avengers, collecting their blood on a mission that would later come back to bite Fury. Fury then somehow isolated the DNA, including Captain Marvel's, creating an incredibly valuable new McGuffin for the MCU and potentially setting up the creation of a hugely powerful new MCU superhero. Marvel effectively revealed the post-credits scene that could have set up Secret Invasion's Fury twist 4 years ago.

Obviously, this scene was probably not planned at the time; it's clearly a retrofit, but it would have worked as Endgame's post-credits scene if Marvel Studios had decided to roll out a "what's next" teaser. It could also have avoided the issue of Secret Invasion feeling too small scale and too disconnected from the mainline MCU, as well as hinting at the presence of the Avengers Skrull in a smart, organic way. Just imagine the set-up of the Battle of Earth clean-up: someone unseen collecting blood from the battlefield, and then their hand/face turning green for the Skull set up. It would have been a huge teaser and Marvel has confirmed a version of those events did happen at that point in the timeline.

Why The Avengers DNA Reveal Should Have Been Phase 4's Big Story

In hindsight, Avengers: Endgame would have promised a bigger Secret Invasion than the MCU has ultimately delivered. Tying the Skrull reveal and the Avengers DNA twist to an actual Avengers movie would have dealt with frustrations about Secret Invasion's execution - and the decision to make it so small scale - but it would have meant an entirely different Secret Invasion and arguably a different Phase 4. Marvel instead decided to focus Phase 4 on a post-Infinity Saga pause point, exploring the fallout of The Blip, as well as introducing unrelated new heroes and opening up the Multiverse Saga. Ironically, focusing those post-Endgame stories on a larger narrative point like Secret Invasion would have helped them feel more structured without actually hurting any of the ideological elements of those movies.

With the world wounded and healing, Secret Invasion would have made sense as a means to further growing dissent, while Fury's betrayal of the Skrulls in his care would have been dropped into its actual context, instead of Phase 5 having to step back into the shadow of Endgame by force. Everything revealed by Secret Invasion feels like the show was released at the wrong time, and the solution of putting it closer to Avengers: Endgame is too good to ignore. That's why the Avengers DNA twist feels so much like the lost post-credits scene - it's almost wishful thinking...