He is Uatu, the Watcher.
He swears to observe everything that will happen or has happened in countless universes.
The Watcher also takes a vow never to interfere with what is meant to be.

However, what if the universe interferes with him, because of a threat that will destroy everything?
Well, that’s different.
The finale features Uatu doing his best Nick Fury to create a special team to stop Ultimate Ultron It leads to one big battle, but also sets up more stories next year.

SPOILERS BELOW

The Watcher (Jeffrey Wright) goes through many universes to get who he needs. The heroes are familiar, from Captain Carter (Hayley Atwell) to Star-Lord T’Challa (Chadwick Boseman). There’s the debut of Gamora, who is out to avenge Thanos’ death. So is Tony Stark in a strange suit, and he survives his appearance. He’s not chosen, though.
However, the Watcher also chooses Killmonger (Michael B. Jordan). That seems strange.

The story also hints on how the heroes are doing. Captain Carter is fitting in her new role as an Avenger, and is best buds with Black Widow (or a version of one). Carter’s fight with Batroc (Georges St. Pierre) is a variation of Captain America’s fight with him in Winter Soldier, and is done very well.
Party Thor (Chris Hemsworth) is doing well as a hero, and likes Las Vegas a lot.
As for Ego (Kurt Russell) planning the future of Peter Quill, he’s stopped by Star-Lord. He got there because of an invasion thanks to Ultimate Ultron. Looks like Ego is destroyed, but maybe he isn’t. That defeat looked a bit too easy.

So, the Watcher and Strange Supreme quickly tell the heroes what’s wrong, and they agree to fight. After all, all universes are under threat.
Still, why is Killmonger there? Even Gamora wonders why.
As for the name of the team, Guardians of the Multi-verse, that seems to be a bit clumsy. It’ll have to do, because it’s just temporary. Knowing this show, maybe not.

The mission is to get the Infinity Stones off of Ultron (Ross Marquand), and crush them thanks to a weapon Gamora has. That’s also odd, because the stones are supposed to exist in a certain timeline. Since this is another universe where they can be anywhere like Dragon Balls, that might explain it.
They decide to concentrate on the Soul Stone. However, Strange Supreme’s absorbing of the Shuma Gorath is having side effects.

Ultron soon arrives, ad the battle is on. The team throws everything at Ultron including Zombies, even WandaZombie. It slows him down but not for long. Fans on the internet expected a longer fight, but it’s telling her magic wasn’t enough.

Then they get to the universe that Ultron destroyed last week, where the Black Widow (Lake Bell) who exists there pulls a gun at them. She relaxes when she learns or her mission. She tells them of the computer virus (aka the computerized version of Zola) that can also stop Ultron.
That leads to another fight over the Soul Stone, but Gamora gets it. She destroys it, and it’s over….right?

Wrong. Ultron says Gamora’s machine doesn’t work in the universe they’re in now. That’s a nice twist, and a call back to the claim the stones don’t work in the TVA. He also thinks if Strange Supreme is killed, it’s over.
Black Widow is able to inject the virus into Ultron’s eye (and says a prayer for Clint Barton), and that lead to a new situation. Zola (Toby Jones) and Ultron fight over the same body. That eventually destroys him….but again, not so fast.

Sure enough, Killmonger steals the Infinity Stones, and claims it’ll be for the greater good (which T’Challa doesn’t believe). Killmonger even appeals to Carter, saying she could be reunited with Steve. KM is a smooth talker, that’s for sure.
Not only that, Zola’s taken over what’ left of Ultron, and accidentally invents MODOK.

Soon, there’s another battle, with Strange Supreme realizing they weren’t supposed to win.
That’s when the Watcher interferes again. Watcher Ex Machina.

He puts Killmonger and Ultron Zola in a pocket universe, which Strange Supreme has to maintain. That’s a bit too tidy an ending, but the comics say something like that was done before. It’s also better than the default (mostly) unhappy ending.
Besides, the Watcher, who has seen it all literally, knew how the plan would work from start to finish. That’s not too different from our Doctor Strange going through all realities late in Infinity War to find a solution. That’s why he chose Killmonger, expecting his betrayal and planning to stop him.

Everyone is sent back, but Carter admitted Killmonger’s offer sounded good. The Watcher says her universe needs her, and she agrees. Just like Steve Rogers, she realizes duty is important.

Black Widow, though, refuses. She asks the Watcher is he considers them as just stories. He says everyone in the multi-verse are people, and very important. Besides, he has a universe who lost its version of Black Widow. She’ll fit right in, which will please that reality’s Fury but not the Loki variant.

It ends with the Watcher reflecting on the past season saying that the multi-verse and its stories are his home, and he will always protect them. That proves he’ll be faithful to his oath, and just narrate next season.

One more thing:  after Captain Carter clobbers Batroc, Black Widow (the other one) shows her something interesting:

and apparently there’s someone inside. So, Carter’s story continues next season.
So, who is inside: either Skinny Steve was put on ice or it’s a descendant? That’ll be interesting either way.

Well, Disney Plus bringing the What If Comic series was one wild ride. Fans expected an anthology series, with Uatu as our Rod Serling. Instead, the season was a lesson on why these stories exist in millions of multiverses, and how they are connected to the Sacred Timeline. We know Peggy and Steve are meant to be, T’Challa is a born leader, and Loki and Killmonger can be big trouble.
Judging from the social media response, fans truly miss Black Widow and want Captain Carter to exist in Earth 616. Maybe something can be done.

According to MCU Direct, next season will center more on the emotional side of alternate realities (like Peggy reunited with Steve, or whoever’s in that HYDRA Stomper). There’s also word the show might get into Shang-Chi (like maybe what if he stayed with his dad) and the upcoming Eternals movie. At least Tony Stark will have better luck in at least one episode, judging from the odd space suit he had.

This show may be a solid part of the Disney Plus/Marvel lineup for sometime, as long as we are all Watchers.
By the way, a special on the making of the show will air October 27th.