**SPOILER WARNING: This story contains spoilers for Black Panther, Marvel comics, and, possibly, Avengers: Infinity War. Read on at your own risk.**
Who is the White Wolf? Black Panther's end-of-credits scene introduces the name, attaching it to a familiar face. But there's much more to the title than you might initially realize.
Our first real look at Wakanda came at the end of Captain America: Civil War after T'Challa (Chadwick Boseman), aka the Black Panther, let go of his hatred — achieving a level of character development that takes most MCU heroes at least three self-titled movies to attain — and welcomed Steve Rogers (Chris Evans) and Bucky Barnes (Sebastian Stan) into the fold.
Bucky declares that he'd rather go back into cryosleep while some scientists figure out what's up with his head than hurt anyone else. We see white-clad nurses and doctors wandering about the room, their mere presence promising a solution for the Winter Soldier. There's no better place on Earth for Bucky to have wound up.
Once Bucky is put under, an emotional but steely-jawed Steve tells T'Challa that Hydra and its allies will probably end up coming after Bucky.
"Let them try," T'Challa intones. The music swells, and the audience gets a sweeping look at the misty forests surrounding the facility and a stone statue of a snarling panther. This mid-credit scene is twofold, guaranteeing a standalone Black Panther film and introducing how Wakanda has managed to keep its third-world ploy up for so long. Most of the world only ever gets to see the wild forest; it's only with T'Challa's hard-earned friendship and respect that Steve and Bucky have been allowed a look at Wakanda's true identity.
Black Panther changes the Wakanda game, and a big part of that comes in the form of T'Challa's little sister Shuri (Letitia Wright). Princess Shuri is easily one of the smartest people in the world, a scientific wunderkind with a wicked sense of humor and the respect of her country. (Side note: We're all just waiting for Shuri to blow Tony Stark's mind, right?)
So, of course, it was Shuri who solved the puzzle that was Bucky's scrambled brain.
The final scene of Black Panther, after the credits have rolled and audiences have sat through the walls of special effects artists' names, shows Bucky coming out of a tent to see everyone's new fave, Shuri. He's snuggled up in a red and blue blanket, and several people shout "White Wolf!" at him.
Sure, Bucky seems to be the only white dude in close proximity, but there's a little bit more significance to the name than that. Before we get into what "White Wolf" means, though, you should probably know the backstory to how Shuri solved Bucky's pesky Manchurian Candidate problem.
Marvel's Avengers: Infinity War Prelude, written by Will Corona Pilgrim and illustrated by Tigh Walker and Chris O’Halloran, answers any questions you might have. It turns out that Shuri's been busy developing an algorithm that will allow Bucky to keep his memories of who he once was — "his loves, his hates, his quirks, his whole personality" — but root out the memories "that have the greatest amount of control over his physical actions ... the ones that have been manipulated due to their deep emotional trauma."
Hence, Bucky strolling around Wakanda with Shuri at the end of Black Panther.
"White Wolf," though, probably refers to the Black Panther villain of the same name — the alias for T'Challa's adopted brother Hunter — first introduced in 1999's Black Panther, Vol. 3 #4. The story goes that Hunter's parents died in a plane crash over Wakanda before he was taken in by the Wakandan royal family. Hunter was raised as T'Challa's brother and believed he had a chance to take the throne after King T'Chaka passed, due to being older than T'Challa. But because Hunter wasn't of royal blood, T'Challa took his rightful place on the throne.
Hunter wasn't too happy about being passed up and went on a rampage that, eventually, ended in a ceasefire after Hunter and T'Challa both realized they were spurred on by love for their country. T'Challa appointed Hunter as the head of the Hatut Zeraze, Wakada's secret police.
And that ... kind of seems like something Bucky Barnes might be good at. That's not to say that Bucky has grounded himself enough in Wakandan society to be granted a leadership position, but it seems that a Sargeant-turned-assassin-turned-hero would be an excellent addition to Wakanda's forces. Trailers for Avengers: Infinity War have shown Bucky (and Steve) fighting alongside T'Challa and a group of male warriors. It's fair to assume that these warriors might be members of the Hatut Zeraze.
If regular citizens of Wakanda know Bucky well enough to greet him as the "White Wolf" at the end of Black Panther, it seems likely that Bucky has become important, maybe even beloved. Part of Hunter's story from Marvel's comics was granted to Erik Killmonger (Michael B. Jordan) in Black Panther — and the rest of that story might belong to Bucky by the time Infinity War comes around. In Infinity War, the Avengers will have to be more united than ever to take on Thanos and his galactic army. Luckily for everyone, they've got the Winter Soldier firmly on their side this time.
After all, Bucky owes Shuri and her family his life.