Avengers Campus is finally open at Disney California Adventure at Disneyland Resort, and Guests can now enter the Marvel Multiverse and explore all the hidden details Walt Disney Imagineers left for them. But between tubes with Gamma radiation run-off and Howard Stark’s parking spot, there is a reference to one of the most tragic events in Marvel Comics history.

Related: The Best Instagram-Worthy Photo Spots at Avengers Campus!

There is much to delight in at the newest land in the Disneyland Resort – especially that incredible Spider-Man animatronic that through the air as they wait to board the new attraction WEB SLINGERS: A Spider-Man Adventure. Guests can even try must-eat food like shawarma just like their favorite super heroes.

But for fans who get lost in the new Avengers Campus, if they check out the map that shows what the land looked like back when Howard Stark first planned to develop the campus they can find even more hidden references to the history of Earth’s mightiest heroes like Doctor Strange, Thor, and Black Widow.

Related: Hollywood Stars Head to Marvel’s Avengers Campus on Opening Weekend

According to the lore of Avengers Campus, Tony Stark’s father had planned the location for Stark Industries to use before it became the C.A.M.P.U.S. (Centralized Assembly Mobilized to Prepare, Unite and Safeguard).

There are many little Easter eggs for them to enjoy in the superhero theme park located in Anaheim. This includes locations for AccuTech, which is a Stark Industries subsidiary that was developing weapons back in Captain America: The First Avenger (2011), as well as a SHIELD quarantine zone.

Related: ‘Avengers: Endgame’ Includes an Avengers Campus Easter Egg!

Guests can also spot a location for Geffen-Meyer Chemicals. This company has never appeared in the Marvel Cinematic Universe, but Disneyland’s Avengers Campus has many Easter eggs from beyond the MCU like lockers that belong to spider-verse characters like Miles Morales and Gwen Stacy.

Geffen-Meyer Chemicals comes directly from Marvel Comics, and it is the sight of one of its greatest tragedies. During the comic book version of Civil War, Captain America/Steve Rogers and Iron Man/Tony Stark argue over super hero registration.

Related: Disney Has Already Made a Big Change to Avengers Campus

In Civil War #3 (2006), the Secret Avengers — led by Captain America — were ambushed by Iron Man at the petrochemical plant. There, Iron Man, Mister Fantastic, and Henry Pym unleashed their unstable clone of Thor, known as Ragnarok, on their former teammates.

In the ensuing battle, the Thor Clone killed an avenger named Goliath AKA Bill Foster. Bill Foster has appeared in the Marvel Cinematic Universe in Ant-Man and the Wasp (2019), played by Black-ish star Laurence Fishburne.

Related: The Avengers Will Text You When You Visit Avengers Campus

It was this moment that set the rest of Civil War into motion. The two sides were unable to come back together at that point. The comic book event was adapted in Captain America: Civil War (2016), which featured an equally gruesome attack. The Vision (Paul Bettany) hit and paralyzed Rhodey AKA War Machine (Don Cheadle).

But what is Avengers Campus referencing with this Easter egg? Is the Thor who is wandering the park actually a clone of Chris Hemsworth’s Thor? It’s probably best to keep an eye on him if you see him wandering over to Pym Test Kitchen for a Quantum Pretzel.

What do you think about this Marvel Comics Easter egg that Walt Disney Imagineering included at Avengers Campus? When will you be visiting?