Avengers: Infinity War is the culmination of 10 years worth of superhero movies. The film builds off 18 previous movies and storylines, and hidden secrets are crammed end-to-end throughout the runtime. The MCU is known for putting Easter eggs in every single movie, from comic book and pop culture references to callbacks within the series itself. Not only do these little bonuses make the films more fun, they can sometimes lead to wild speculation about where the series is headed. They aren't all just goofy jokes.
This extreme attention to detail makes it almost impossible to keep up with every little reference, and even the most astute viewers are bound to find things they missed in Avengers: Infinity War. Obviously, the film makes extensive references to the comic books that inspired the film, but not every Avengers: Infinity War Easter egg comes from the comics. While calling Drax Mr. Clean is a reference almost everybody would get, we're willing to bet there were a few others that went over your head.
Black Panther Yells "Yibambe!"
Most MCU fans are aware of the Wakandan war cry, "Wakanda Forever!" What they may not have noticed was Black Panther's cry of "Yibambe" in Infinity War. This isn't some vague, African-sounding word that the producers came up with for the film, it's actually from the Xhosa language spoken by some 20 million Africans. It means "hold" and is a call to rally the troops and stand together in the face of overwhelming odds. On some level, this probably demonstrates Wakanda's newfound willingness to interact with other countries in Africa and imbue their culture with that of other African descended cultures around the world.
"Rubberband Man" Has To Be Playing On A Zune, Is Also From A Father To Son
At the end of Guardians of the Galaxy Vol. 2, Yondu Udonta gives Star-Lord a Zune music player that comes pre-packaged with a whopping 300 songs. This is important because Star-Lord realizes that Udonta is the closest thing he's ever had to a father.
When we first see the Guardians in Infinity War, they're listening to the song "Rubberband Man" by The Spinners. It's safe to assume this is playing off of Star-Lord's fancy new Zune, which means that it was one of Udonta's favorite songs. This is interesting because the story is that "Rubberband Man" was written by producer Thom Bell for his own son to help him with his self-esteem because of his weight. This also makes the scene where the crew makes fun of Star-Lord for his perceived weight gain even funnier.
The Collector Captured A Never-Nude
Avengers: Infinity War isn't the first thing the Russo Brothers have directed. They've also directed Captain America: Winter Soldier, Captain America: Civil War, and several episodes the hilarious sitcom Arrested Development. As such, the Russo Brothers love putting odd references to their time on Arrested Development in their Marvel films. For example, the Bluth family's stair car made an appearance in Civil War. In Infinity War? They crammed Tobias Funke into a glass tube.
As the Guardians sneak up on Thanos's interrogation of the Collector, Gamora walks past a glass cylinder that appears to contain a mustachioed blue man in jean shorts. It doesn't appear to actually be David Cross in there, but the reference is clear. The Collector has managed to acquire one of the only known "Never-Nudes" in the entire universe.
Thor's Muzzle Mirrors Loki's From The Avengers
During the first fight scene in Infinity War, Ebony Maw uses his magical manipulation of metal to imprison Thor. Thanos uses Thor's immobility to talk to Loki and, ultimately, to murder him right in front of his brother. So that Thor cannot argue to save his brother's live, Maw affixes metal around his mouth, creating a muzzle. That muzzle looks almost exactly like the one they put on Loki at the end of The Avengers to keep him from persuading anybody or performing any tricks. It's a sad call-back because Loki has finally become a good person, but Thor can do nothing to help him.