Warning! This portion may contain spoilers for Marvel's What If..?. Read at your own risk!
Marvel's What If..? Episode 8, What If.. Ultron Won?, definitely sets the tone for the upcoming finale and the whole run of the canon series finally coming to a culmination of all that has happened. The ending opens all possible doors as Uatu makes a decision that, albeit against his will, could be the only way to save the multiverse as we know it.
The Ending of Marvel's What If..? Episode 8 Explained
Just as Ultron got all the Infinity Stones, he eliminated almost the whole universe and he sat in his quiet victory, the peace he calls his purpose, he became aware of other otherworldly beings in existence and The Watcher was surprised when Ultron heard and saw him peeking through what looks like glass, where Uatu has been watching various alternate realities happening.
Ultron seemingly becomes a being more supreme than others that he has awareness of the presence of Uatu, something that The Watcher is not expecting at all. Ultron found out that other universes exist, more places to wreak havoc, more timelines to destroy and silence, and he planned to find Uatu wherever he hides.
Ultron and The Watcher come face to face as Ultron was able to break through his place and they had a battle. Uatu's strength is incomparable that he could face Ultron who wields all six infinity stones. When Ultron mocked Uatu's will, he transformed into the supreme being that he is, telling Ultron, "You cannot compute the power of my will."
Still, Ultron emerged victoriously and The Watcher went into hiding, one away from Ultron's eyes. He hid in the pocket universe, one that became the prison of Doctor Strange Supreme after he devoured the powers of other beings and there, Uatu was convinced by the evil Strange that The Watcher would need to break his oath of non-intervention in order to save the multiverse as we know it from Ultron.
It is speculated by many fans and viewers that Episode 9 will be the culmination of all the episodes of the whole series given that it is the finale of the show and a lot are excited about the arrival of the "Guardians of the Multiverse" as they call it. It is expected that heroes from different timelines would come together to fight Ultron.
Should there be a new team, it would probably be composed of Black Widow from the same timeline as Ultron, Captain Carter from Episode 1, Killmonger as Black Panther from Episode 6, T'Challa as Star-Lord from Episode 2, Party Thor from Episode 7, and Doctor Strange Supreme from Episode 4. Others suggest that Hulk or Spider-Man from Episode 5 would be there, as well as Gamora who wields the double-edged sword of her father.
What do you think will happen in the finale of What If..?