Joss Whedon once said that there “aren’t a ton of Easter eggs” in Avengers 2, saying “It’s so hard for me to make a movie, especially this movie, I don’t spend a lot of time going, ‘You know what else would be hilarious?!’” But, it turns out that Whedon just couldn’t resist himself and for those paying very, very close attention, you’ll notice a clever nod to the Buffyverse.
During Thor’s visions of Asgard when all kinds of trippy stuff is going down, at one point you catch a glimpse of three masked men in the archways. The man on the left is wearing a wolf mask, in the middle a ram, on the right is a hart (a medieval word for a stag). Wolf, ram, hart. And if you’ve ever seen Whedon’s Buffy the Vampire Slayer spinoff, Angel, you know where we’re going with this.
Here’s a screenshot of the scene in question:
Whedon confirmed on the Age of Ultron director's commentary that this was a sly nod to Angel, and the villainous Wolf, Ram & Hart.
On Angel, The Wolf, The Ram and The Hart were an ancient trio of true demons who, in present day Earth, are “senior partners” at the Los Angeles law firm Wolfram & Hart. Through this organization, they enact their evil will, representing murderers and other demonic individuals.
So, there you have it. A special Buffy-centric easter egg from Joss Whedon himself. For even more Avengers 2 easter eggs, check out our master list here.