Movie watch parties have popped up all over since we’ve been a nation (mostly) under quarantine lockdown. With movie theaters on temporary pause, people have been getting their film fix by joining in on Twitter livetweets and Instagram livestreams for different movie watches. The most successful ones by far have been the ones spearheaded by Marvel directors, such as James Gunn’s watch parties for Guardians of the Galaxy Vol. 1 & Vol. 2 or Taika Waititi with Thor: Ragnarok.

But the biggest one so far was the recent Avengers: Endgame watch party with directors Joe and Anthony Russo, who shared behind-the-scenes tidbits via Twitter while also doing an Instagram livestream. Robert Downey, Jr. even hopped on their livestream to watch with fans for a bit. Longtime Marvel and Endgame screenwriters Christopher Markus and Stephen McFeely also participated, taking over the Comicbook.com Twitter feed with their own trivia.

Here are some of the most interesting things we learned during the Avengers: Endgame quarantine watch party.

1. They Snuck Into The Theater On Opening Night To See The Crowd Reaction

Talk about a gratifying moment as a filmmaker. I’ve written before about how another moment in Endgame is the sort of scene that captures everything about why we go to movies, and the crowd reactions here are just another example. The Russos might not be the ones who started the whole chain of events – that would be Iron Man director Jon Favreau, who then passed the Avengers baton to Joss Whedon – but they’re certainly the ones who finished it, at least the Infinity Saga arc that built through the first three phases. No wonder they teared up. I can’t imagine what it would be like to have your magnum opus received with such enthusiasm and warmth as the ecstatic audiences on Endgame‘s opening night.

2. They Shared A Videos From RDJ’s & Chris Evans’ Last Days On Set

It’s hard to overstate what Robert Downey, Jr. and Chris Evans have meant to Marvel as the two pillars of the MCU. Iron Man may have started out as the more popular character, but things shifted after Winter Soldier, and soon, Captain America was just as beloved. It’s hard to imagine anyone else playing Steve Rogers or Tony Stark now. It’s lovely to see the love and respect the crew has for the two actors.

3. And They Also Shared A Video From Brie Larson’s Very First Day On Set

Some fans might not know this, but Brie Larson actually shot her scenes for Endgame before shooting Captain Marvel. The result was that she and writers were still trying to figure out Carol Danvers’ personality and mannerisms in the film that technically took place decades after the events of her solo movie but were shot before. She’s said before it was a little intimidating to walk on set with the tight-knit cast feeling like the new kid in school, but it looks like they were excited to have her, with Scarlett Johansson giving her a warm hug.

4. ‘Fortnite’ References Abounded

One of the laughs in the movie was the scene in which a depressed Thor and Korg were playing Fortnite against a troll named “Noobmaster69.” When someone asked the Russos who Noobmaster really was, they joked and said it was “M&M,” i.e. Markus and McFeely:

On top of that, the Creative Director of Fornite developer Epic Games, Donald Mustard, even had a cameo in the final battle scene as one of the wizards of Kamar-Taj:

5. Recreating Scenes From Previous Movies Was One Big Reunion

They shared a treasure trove of pictures from the scenes in Endgame of the Avengers revisiting various points in their past.

What a cast Marvel has assembled over the years. Truly remarkable.

P.S. They’re joking about Rene Russo – she’s definitely not their sister.

6. But They Were Also A Challenge To Recreate

Like trying to land the same locations or ones that looked similar

To working around the challenges of those locations being in use

Or having to warn non-production workers who might be present

To the tiny continuity details they needed to take into account

It’s hard enough to pull the Marvel Cinematic Universe together. Adding in the extra twist of them going back and revisiting scenes from previous movies made it even more of a challenge. You know eagle-eyed fans would have spotted any continuity errors immediately. To their credit, Marvel pulled it off.

7. Sam Wilson Was Meant To Be The Next Captain America Almost From The Start

Some fans are still upset that it’s not Bucky taking up Captain America’s mantle. But, like I wrote last week, that just wouldn’t make sense. Nice to see Markus and McFeely agreed with me and for the exact same reasons.

8. Quite A Few Things Changed From The First Draft & Other Ideas Didn’t Pan Out

But still, no matter how many times they ended up rewriting scenes…

Or still rewriting them in their sleep…

They’re still annoyed by tiny details they missed

Even screenwriters from the biggest movie franchise in history make mistakes. It’s interesting to wonder what they’d do differently if they had another crack at it, knowing what they know now.

9. But A Surprising Number Of Scenes And Beats Survived From The Very First Draft

Even with all the necessary changes, the huge emotional beats and major connective tissue stayed true to the end. It’s just a testament to how well the longtime screenwriters know the universe they’ve created – how well every person involved knows this world and these characters, really.

10. Their Wrap Party Cake Was Absolutely Epic

That’s a Black Panther symbol on the bottom right, but if I’m being honest with you, I got very excited for a moment because I thought it was Daredevil. Also, I need this cake.

The entire thing is full of more nuggets and tidbits, so if you’re a Marvel fan, I urge you to read back through the Russos’ Twitter feed or CB’s feed. Fascinating stuff.