Marvel’s What If...? series, based on the original What If...? comics, has opened the door to the numerous possibilities in the multiverse for MCU fans. The audience can now see characters they’ve loved for over a decade in a new light that makes the characters feel fresh. From Peggy Carter's rebirth as the super-soldier Captain Carter to Prince T’Challa's acquisition of Star-Lord's mantle, to the many more that are on their way, each of these characters comes with a brand-new timeline for the MCU. Small decisions that seem insignificant send the universe on entirely new paths.
However, the character with the most impact on the main timeline thus far has got to be Prince T’Challa in his role as Star-Lord. Instead of becoming a space-pirate like Peter Quill, T’Challa used his diplomatic training to bring a new age of peace to the galaxy.
6 Infinity War Never Happened
Probably the biggest change to the MCU timeline is that the large-scale conflict that occurred in Avengers: Infinity War never happened. The race against time with Thanos trying to collect the six Infinity Stones that eventually led to the Blip event may have been completely avoided.
Thanos appears in the series as a somewhat reformed individual who sees the error of his original plan, though likes to remind everyone how 'efficient' it was. Instead of being the Mad Titan known for wiping out half of the universe’s population, he has chosen to abandon his life of atrocity and joined the Ravagers with T’Challa, protecting the innocent.
5 Nebula Is Fine
Alongside many other improvements to the galaxy, Nebula, the adopted daughter of Thanos, has a much better life. Though she is still his adopted daughter, it can be assumed that not only did T’Challa save her much earlier than the Guardians did in the original timeline, but she has had the time to completely recover from her trauma.
It can also be assumed that she has even gained a certain level of status in the underground intergalactic crime scene. She is introduced as a fixer for T’Challa, helping him arrange various jobs in advance.
4 Ronan Was Stopped Much Earlier
Ronan is never seen during this episode, but it is clear that he has nowhere near the amount of power he had in the original timeline. In this new timeline, Drax is a simple bartender who never sought to avenge his family's deaths, because his wife and daughter are still alive. And, based on how he reacts when he sees Star-Lord, it is possible that Star-Lord was the one who defeated Ronan years before Quill and the Guardians confronted the rogue Kree.
With the Kree Empire decimated by Captain Marvel decades before, and without Thanos to support him, Ronan was never able to become a deadly warlord the way he was in the main timeline.
3 The Avengers Lost The Battle Of New York
During T’Challa’s final conflict with the Collector, he opens a display case showing many of his collected artifacts from across the galaxy. Two important elements in this collection are Thor’s hammer, Mjolnir, and Captain America’s shield. This could either suggest that both Steve Rogers and Thor Odinson died at separate points in their life, or they died during the Battle of New York in the first Avengers film.
Since it is unclear when Thanos reformed, it is possible that Star-Lord’s interactions with the Mad Titan caused him to improve his army, leading to the Avengers losing in New York. From there, it is not hard to imagine how the Collector managed to acquire these trophies.
2 The Ravagers Are All Reformed
Though he was young when he was taken from his home planet, T’Challa was raised to be a good person. He was granted the best education that Wakanda could offer and trained to one day replace his father as a diplomat. Those skills would come to be his most powerful weapons. Where Peter decided to leave the Ravagers and hunt treasure on his own, T’Challa made the decision to stay and reform the Ravagers.
In this timeline, the Ravagers have cleaned up, metaphorically and physically speaking, and they use their talents to be the Robin Hoods of the galaxy, stealing from the rich and powerful and giving to the poor and needy. Though they are still professional criminals, T’Challa and the Ravagers only ever use their talents for good.
1 Without Peter Quill, There Is No One To Stop Ego
Kurt Russel reprises his role as Ego the Living Planet for a short cameo at the end of the episode to show how even though T’Challa solved most of the galaxy’s problems, Peter’s absence still has a serious impact. Since he never became Star-Lord, Peter never left Earth, meaning that it was much easier for Ego to find him.
Without the Guardians to stop him, it is likely that Ego’s plan will play out completely unnoticed by the likes of Star-Lord since Ego’s homeworld doesn’t show up on any maps. This universe could be doomed, destined to become an eternal portion of Ego’s hivemind.