What's going on with 'All Hail the King?
"All Hail the King" uncovers that Trevor Slattery (Ben Kingsley) isn't really Mandarin and he had been lying about his job in the film, as per ComicBook.com. The film uncovers that Trevor involved the Mandarin's name as a kind of distraction for the AIM gathering's strange plans.

"'Wonder One-Shot: All Hail the King' (2013) is recently added and has a first page pennant in front of Trevor Slattery's return in 'Shang-Chi.' The short film specifies the genuine Mandarin, closes with a snare for 'Shang-Chi,' and was initially delivered as an exceptional element on the 'Iron Man 3' Blu-beam."
Also, this is the way the Marvel UK YouTube page depicts it:

"After the occasions of Iron Man 3, Trevor Slattery is presently a notorious symbol. He's likewise secured in a high-security jail. Fortunately, his recently discovered profile has welcomed him VIP and assurance within - and the entertainer has happily consented to a top to bottom profile with a narrative movie producer."

All Hail the King projects more profundity on Kinglsey's job in the Marvel Cinematic Universe that turned into a subject of discussion since the projecting declaration was imparted to general society. The short follows Trevor right after his capture toward the finish of Iron Man 3 as he changes with his new detained way of life. The episode is drawn nearer from to a greater extent a narrative style viewpoint as Trevor annals Iron Man 3 according to his perspective and his inevitable comradery with The Ten Rings fear monger association. All Hail the King strolls back and gives a more provocative gander at Trevor from a more private casing of reference.

While thinking about the high volume of Marvel content delivered at such an anxious and efficiently manufactured rate, it's difficult to without hesitation express out loud whatever is - or isn't - ordinance. Wonder Studios produces Marvel One-Shots, and it highlights accepted characters, implying that it tends to be assumed that the short is viewed as official in artistic legend. It offers sufficient individual understanding that All Hail the King could resound as group in the Marvel Cinematic Universe. There's sufficient express detail that upholds the world-building and advancement of different characters included artistically at the hour of delivery.

More than anything, obviously, All Hail the King strolls back on the missteps made around The Mandarin through Marvel's first endeavor to highlight him as a scoundrel. This is a significant note when thought about with the way that Marvel Studios made a guarantee of variety and incorporation in its ventures, something horribly ailing in the Infinity Saga. The Mandarin's depiction (or, all the more accurately, deficiency in that department) in Iron Man 3 was, for some, a lost an open door to depict Asian and Asian-American societies and characters in the establishment. Curiously, Shang-Chi was initially intended to be presented in Phase 1, yet it eventually assumed control north of a time of MCU movies to at last bring an Asian superhuman into the overlap.

Why this matters for 'Shang-Chi'
I will not uncover everything, except "Shang-Chi" zeros in a ton on the legend of the Mandarin and the 10 rings, and it even has a couple of callbacks to "Iron Man 3."

Finding out about the Mandarin in "Wonder One-Shot: All Hail the King" will just assist individuals with having a superior comprehension for what occurs in "Shang-Chi," and getting the secret of the 10 rings.