WARNING: MAJOR Midnight Spoilers in this post!
The Story of the March on Quel'Danas
In the lead-up to this cinematic, we first fight our way through the March on Quel'Danas raid. Before we can defeat L'ura at the Sunwell, we have to clear out the Plateau around it of enemies. While the armies around us battle, we take the fight to Belo'ren, the last child of the phoenix god Al'ar from Tempest Keep. His egg had previously soaked in the power of the Sunwell over the years since its rebirth, but since its transformation into the Darkwell, the Void has also suffused into him and turned him into a volatile enemy we are forced to fight.
After battling both his Light and Void halves and preventing them from being reborn via his phoenix egg, we leave Belo'ren's egg to hopefully recover long-term, and join Vereesa Windrunner and Arator in battling L'ura at the Darkwell. Using the connection she has to Alleria from her time spent captive inside the elven ranger, L'ura incapacitates both Vereesa and Arator with torturous memories, and invites us in to our doom at her hands.
L'ura yells: You are your mother's son... a constant reminder of her failure. You sicken her.
Arator yells: N-no... liar!
L'ura yells: You look up to your sister so highly... she only looks down on you. A weak little girl to be pitied.
Vereesa Windrunner yells: A-Alleria... I can't...
L'ura yells: You... I would not be here without you. My thanks.
L'ura yells: Come to me. Accept your oblivion.
Sylvanas' Return
While the fight ends with L'ura dead, the Darkwell remains open, and Xal'atath remains unharmed. As she moves to attack the still-recovering Vereesa and Arator, her spell is interrupted by none other than Sylvanas Windrunner.
Still using the powers of the Maw, Sylvanas' sudden presence threatens Xal'atath enough to force her to close the Darkwell and retreat through its depths, ending her invasion... for the moment. Based on her rather nonchalant attitude, it is likely that Xal'atath succeeded enough in her goals that closing the Darkwell at that moment did not ruin her plans, and with her exit having a distinct downward animation, it's likely that she was sending her Devouring Host not to invade Silvermoon, but towards her true prize: Azeroth's Worldsoul.
In the following moments, we see Vereesa in a state of clearly mixed emotions. Sylvanas' actions in recent expansions are well known, from the burning of Teldrassil to her alliance with the Jailer in recreating the universe. To most people, she is a wholly irredeemable monster, but Vereesa was one of the few who had hope that Sylvanas might find her way back to righteousness amidst her penance at the end of Shadowlands.
Vereesa Windrunner says: For so long, there had been little more than hatred and malice in our sister's eyes. To at last see a glimmer of the Sylvanas we knew...
Alleria Windrunner says: I had ceased hoping for such a thing. I am pleased we had a chance to speak with her, Vereesa.
Vereesa Windrunner says: I only wish we'd had more time!
Alleria Windrunner says: As do I. But if she stays true to her word and sees this obligation through, perhaps one day we will.
Vereesa Windrunner says: It will never be like it was before. The pain she inflicted upon the kaldorei... upon the world... how could she ever answer for it?
Alleria Windrunner says: I'm not certain she can. But if her penance brings any measure of peace to those she wronged, at least it is a start.
Vereesa Windrunner says: You're right, Lady Sun. Our family has endured so much darkness. We must find a way to cling to hope.
Alleria Windrunner says: Yes, Little Moon. Mother, Father, Lirath... they are only memories. We thought our sister was as well. But now... we shall see.
It seems Vereesa does ultimately deem her sister as having set herself on the path of atonement, giving her a hug that surprises even Sylvanas. Despite her words to Arator during the Midnight prologue patch, Sylvanas seems to have found a way to leave the Maw for a brief moment, albeit with some kind of cost. Her stay at the Sunwell is far from permanent though, and she ultimately has to return to her penance.
Nevertheless, Sylvanas arrived to save her homeland as its Ranger-General "one last time", according to her. It is likely that this is Sylvanas' final coda of relevance for the story of Quel'thalas moving forward, having saved its people from annihilation yet again.
In many ways, the Blood Elves seem to have a blind spot for Sylvanas' actions in undeath, good and bad. Despite the salvation she offered them with the Forsaken during The Burning Crusade and the annihilation she nearly brought them to as Warchief of the Horde, the action she is most remembered for is the last one she gave in life: the defense of Silvermoon. Having done so yet again, there is a certain tragedy to Sylvanas' own people being unaware of her actions to defend them against Xal'atath.
In the end, Vereesa finally gets to see the return of the sister she once knew, if only for a few moments, but it is likely only a small balm against the loss of their other sister, Alleria.
The Void's True Enemy
While Sylvanas' brief family reunion is heartwarming, the threatening nature of her mere presence fending off Xal'atath brings up a number of questions. On the surface, Sylvanas is simply one undead elf, with a lingering connection to the powers of the Maw she once used to aid the Jailer. To the Void, however, Sylvanas seems to represent a long-standing fear they have of the force of Death.
In her taunt to Xal'atath, stating that "Death comes for all", Sylvanas references her line from the cinematic where her modern character arc first began with her ascension to the role of Warchief in Legion, but it also references the whispers from the Void that Alleria received when she first reunited with Sylvanas in the Three Sisters comic.
At the time, these lines were almost certainly referencing her alliance with the Jailer and their plans to reshape the cosmos, but with her continued use of the Maw's powers, the Void might still fear Death and the impact someone like Sylvanas would have with its powers. This idea is further corroborated during The War Within, where Xal'atath's brief encounter with Ve'nari brings up the relationship between the Maw and the Void's fears.
Ve'nari says: Enough! Make sure he succeeds. I have been to the Maw. I know what the Void fears.
Xal'atath says: I'm sure you do.
What danger might the powers of the Maw still pose, though, and what would Sylvanas' role be in all this to make Xal'atath fear her? Well, her other lines imply...
The Shadowlands Aren't Quite Right
Sylvanas' reasons for not lingering in Quel'thalas also extend beyond her intent to return to penance. In addition to continuing to serve her sentence, she also intends to discover the truth behind the Shadowlands. According to her, the Shadowlands are "not at all what they seem", and she hopes to discover that truth "before the end begins".
Vague Jailer-esque statements aside, this is not the first time the unnatural nature of the Shadowlands has been brought up by Sylvanas. Back in patch 11.2.7, she mentions to players in her optional conversation that the Shadowlands are "too ordered", and that she cannot yet return to Azeroth because of it.
Sylvanas Windrunner says: You have noticed, have you not? The Maw. The Shadowlands. All of it. The question that has plagued me since the Jailer's demise.
Sylvanas Windrunner says: I know the truth of death better than most. This? It is too convenient. Too ordered.
The implications of these statements are potentially wide-reaching, bringing up the possibility that the unnatural system of soul sorting and segregation imposed on the afterlife may have been created by the Titans. They are the prime beings of 'Order' within the Warcraft universe, and even during Shadowlands, many players pointed out the similarities between how the Titans ordered Azeroth and how the First Ones ordered the afterlives.
While this is likely Sylvanas' last appearance in Midnight or the ongoing elf storyline, it seems more and more likely that she will make her proper return to the story in The Last Titan, when the ongoing story about the Titans and their influence on Azeroth's Worldsoul come to a head.
The Final Chapter
After the cinematic concludes, Vereesa and Arator are joined by Liadrin, and they comment on what remains -- or doesn't remain -- of the Sunwell's power.
Vereesa Windrunner says: We've won, but the Darkwell remains.
Lady Liadrin says: What was wrought here cannot simply be undone. The Light is all but consumed. I barely feel the well's power.
Arator says: We can't leave it like this--the wounds the Void left behind must be healed.
Arator says: There's more to be done, but I think we've earned a moment of respite. Let's head back to Silvermoon for now.
As mentioned by Arator in the previous campaign chapters, the elves of Azeroth have been rallied not only for their martial prowess, but their magical expertise as well. Next week's chapter will likely pool their diverse experiences with fonts of power to figure out how they can fix the Darkwell's lingering corruption, and if the Sunwell should be restored in its place.
