So we've come to the end of Loki. Not the series finale, but the season finale, as revealed by a card mid-credits:
Most of this episode took place in the Citadel at the End of Time, where Loki and Sylvie finally tracked down the being behind the TVA curtain. He was only identified as "He Who Remains," but according to various sources, he is a variant of Immortus/Kang the Conqueror. Apparently Kang is going to be the next Marvel Big Bad. He invites Loki and Sylvie to sit down at his desk and talk (after demonstrating to Sylvie that he knows exactly when and how she will try to stab him and can blip out of range, at least until everything passes what he calls the "threshold." This is a bit fuzzy and not explained well, but it seems to be a point where the multiverse, perhaps knowing Kang is going to die, stops feeding him information and starts coming apart), and explains how he got to where he is. In the 31st century, the original Kang discovered the multiverse and his variants. The different versions of himself all cooperated for a while, but the nastier ones started the multiversal war that nearly wiped out all of existence. So the TVA Kang weaponized the devouring purple cloud seen in episode 5, Alioth, killed all of his other selves, and set up the TVA to continuously prune the timelines and prevent other versions of himself from coming into existence. "He Who Remains" has been the master manipulator behind the curtain for millennia, and now he wants nothing more than to retire and/or die...and he has selected Loki and Sylvie, allowing them to win through all the obstacles in their path to reach him, to take his place. If they let him live and take over, the TVA and the state of the multiverse will continue as before...but if Sylvie kills him, the multiverse will fracture, and all the bad versions of Kang will arise once again.
(Kang is played by Jonathan Majors, late of the HBO series Lovecraft Country [and just nominated for an Emmy for his performance], and he does a fantastic job. As is the norm with this show, it has a lot of sitting and talking--in this case, nearly the entirety of the He Who Remains scenes. Majors has to create a full-blown, layered character in about fifteen minutes of screentime: a master conqueror/manipulator simultaneously riddled with hubris and depression, an egomaniacal god who wants to rule everything and a tired old man who only wants to fade away. I've said all along that the strength of Loki's cast covers a multitude of talky, expositional sins, and Majors is no exception.)
Naturally, this does not sit well with Sylvie. She has devoted decades, possibly centuries, of her life to running and hiding in various apocalypses long enough to survive, stay ahead of the Time Variance Authority, and orchestrate her revenge (as she tells Loki before they enter the citadel, "I was pruned before you even existed"), and she is determined to kill He Who Remains. She says he is nothing but a liar and refuses to believe what he is telling them. Loki, on the other hand, sniffs out a few grains of truth amongst all the bullshit, and tries to talk her down. He doesn't even tell her not to kill Kang--he just asks her to consider the options, saying what happens if Kang is dead and something even worse comes along? Sylvie, maybe recognizing that Loki is making a little too much sense here, accuses him of wanting the "throne"--presumably the leadership of the TVA--for himself. They fight, in a neatly choreographed battle, and Loki finally throws away his sword and faces Sylvie with nothing but his words. He says "Stop" several times and continues: "I've been where you are. I've felt what you feel. Don't ask me how I know. All I know is I don't want to hurt you. I don't want a throne. I just want you to be okay."
Sylvie stops, for a moment, and you can tell Loki's words are getting to her. Because she suddenly kisses him. Some other reviews of the episode have simply gotten this wrong. When I watched the episode the second time, I could see it--Loki does not kiss her (though I'm sure he wanted to); she kisses him. And I'm sure she did it because a) she wanted to stop him from saying anything more that might cause her to back off; and b) she wanted to distract him long enough to grab He Who Remain's TemPad and remove Loki from the playing field. Which is exactly what she does. She pulls away, tells Loki, "But I'm not you," opens up a time door and pushes him through it, sending him away from the Citadel and into (as we will see) another timeline. Then she turns and runs Kang through with her sword. He tells her, "I'll see you soon," as he dies, and behind him, we see the Sacred Timeline fracturing into a million pieces.
This is the bomb that has exploded in the heart of the MCU, and Loki knows it. He also knows he has been betrayed, and we can see the weight of both things settling on him (through another bit of Tom Hiddleston's marvelous acting). Finally, he runs through TVA headquarters--since that's where he ended up--to find Mobius and explain what happened. But Mobius doesn't recognize him. He doesn't even recognize him as a Loki--he thinks he's an analyst from another department. Loki, suddenly realizing he has landed in an alternate timeline where maybe he has never existed, turns to look at the TVA's multi-story inner courtyard, where a massive statue of He Who Remains has suddenly taken up residence.
This is what I mean about the supposed star of the show getting a bit of a short shrift. I think this season could have done with at least another episode to better flesh out the characters and explain what is going on here. (And apparently that nearly came to pass--according to one of the writers, Episode 2 almost contained more of Sylvie's backstory. Talk about a missed opportunity.) I think Loki is the second best of the Marvel series so far, but I also think there are a lot of things they could have done better. I hope the second season will address them.