Note: This article contains plot points in Black Panther.
There’s a very good chance the last Infinity Stone is in Wakanda. Black Panther is one of the most self-contained films in the Marvel Universe franchise, ignoring the crowded world of the Avengers save for a Bucky Barnes cameo tucked into the second post-credits scene. That helps make it not just a great Marvel film, but a great film, period, without the qualifier. Black Panther’s animated opening illustrates Wakanda’s history, which begins with a meteor made entirely of vibranium crashing into Eastern Africa. This rare and valuable metal is the resource Wakandans use for their impressive technology, including much of the city of Wakanda and T’Challa’s kinetic-energy responsive suit.
But the concept of a metal alone being solely responsible for such technological marvels is hard to swallow: Vibranium may be from outer space, but it’s still just a metal. But what if there’s something else in that meteor that makes vibranium powerful in the first place? If there’s an Infinity Stone residing within the meteor, imbuing the vibranium metal with Infinity Stone powers, the Wakandans’ technology starts to make a lot more sense.
Technology and Infinity Stones go hand-in-hand; for evidence, look no farther than Captain America: The First Avenger. The power of the Tesseract (which holds one of the Infinity Stones called the Space Stone) enables Hydra to build weapons and vehicles otherworldly in their power and capabilities in just a couple of years during WWII. With the help of an Infinity Stone, it stands to reason that the Wakandans would be able to create their advanced city with its excellent public transportation system over the course of a couple thousand years, and be the resource Shuri uses to create her brother’s powerful suit that fits in a necklace.
The other major clue supporting this theory, and probably the most obvious, is the king of Wakanda’s ability to visit the ancestral plane. T’Challa and Killmonger both go to this spectral territory to speak with their ancestors by ingesting the seed of a heart-shaped herb found only in Wakanda. The ability to travel to the ancestral plane makes the most sense if the Infinity Stone at the center of the meteor is in fact the Soul Stone, as this Stone possesses the ability to manipulate the souls of both the living and the dead while enabling access to an idyllic pocket universe. This pocket universe would also explain the Wakandans’ ability to cloak their city and resources from the rest of the world. If the Soul Stone is in the vibranium meteor, affecting the land around it, it’s logical that the glowing herb growing out of that ground would provide strength, alternate projected realities, and the ability to interact with the souls of the dead.
Yes, director Ryan Coogler has claimed that the Soul Stone isn’t in his film. In an interview with IGN he says:
I love the Infinity Stones as much as any comic book fan, it’s just Wakanda already has its thing, which is vibranium. For us, that was special enough, so to throw in something like another special thing didn’t feel right. It felt like we should stick with our one MacGuffin for the country and explore that, let that be the important thing because, frankly we didn’t need to have another piece like that.
If the Infinity Stone and vibranium go hand in hand, though, Coogler wouldn’t need to include its presence in Black Panther; by introducing vibranium and the meteor as crucial elements of Wakanda’s technology, he elegantly side-steps the necessity of addressing the Infinity Stone question. Vibranium could be establishing the Infinity Stone’s presence in Wakanda, without ever calling it out by name.
Otherwise, why would all of the Avengers be running together with the badasses of Wakanda in what looks like an epic battle with Thanos in the Avengers: Infinity War trailer?