Leaked Set Photos Reveal New Hero
Black Panther 2 set photos reveal the return of Wakanda Elders and Ancestors including M’Kathu, M'Baku and a neccessary change in the whole movie due to loss of Chadwick Boseman could result in Killmonger's return.
Iron Heart Shall Be The Name!
The New Age Iron Man will be called the Iron Heart (Riri Williams) played by Dominique Thorne - spotted on Black Panther Set quite a few times, after her introduction in Black Panther 2, she'll head straight to her Disney+ Series.
Iron Heart A Wakandan Lady?
Riri Williams could be a Wakandan girl given her genius mind and a whole new Iron Man suit of her own which she built possibly with the help of Vibranium and other Wakandan Genius like T'Challa's lil sister Shuri.
Killmonger's Return Is Not Welcomed
Killmonger should not return as it is a direct insult to Black Panthers legacy, both their ways were very different. Killmonger chose death over peace and hence why not fit for return, but rewriting the story due to loss of Chadwick could bring him back.
A "Young Hero" Shall Prevail
Leaks are that Killmonger could return but only in ancesral plane where the tribe meets their ancestors to seek guidance. Here, to guide a "Young Hero" as quoted by Marvel Creators themselves, this "Young Hero" could be anyone.
MCU's Own Aquaman!
Wakanda may also face a war with the whole new civilization: The Lost Kingdom Of Atlantis, led by Namor The Sub-Mariner, not particularly a villain but sure an Anti-Hero, this way MCU will get their own Aquaman.
A War Could Save The Movie
A war makes sense because what good is a Black Panther movie without the Black Panther himself, as MCU has made it clear they won't recast T'Challa. So an action-packed war with awesome techs from both civilization is the only thing that could save this sequel.