In this article we return to talk about Alicization. If you are not familiar with the series, we recommend you to retrieve the reviews of the other episodes to this link.
As with many stories, before the climax and triumph of the heroes it must precede the fall to the lowest point: in the start towards the conclusion of the adaptation of Volume 17, the events of Underworld are dizzying to that point.

Alicization: Sometimes they come back

Like the previous episode, Code: 871 limits itself to transposing a handful of pages integrating with itself, as planned, those events skipped in the last episode to rearrange them in a way that makes sense.
Fortunately, these changes have no effect on the continuation and actual conduct of the story while leaving the useful contents of the five main sequences of this episode intact.

Code 871 - VVVVID

One of the most important is undoubtedly concentrated in the heart of the battle, with Asuna gradually demoralized by the slow but inexorable defeats suffered by her battle companions, crushed by the numerical superiority of the enemy forces.
The importance of this sequence, however, is centralized on Siune, an old companion of the Sleeping Knights guild and on PoH, who is the main antagonist of the battle scenario between the Human Empire and foreign players: the first, although the series has not even mentioned during the adaptation of Mother Rosario the detail is in fact half Korean (also guessed from her name in real life) and this fact allows her to appeal, at least for a few moments, to the common sense of enemy players, especially the already seen Moonphase and Xie Xie who are increasingly suspicious of the circumstances of the events.

This is where PoH reveals his manipulative abilities first, and then something extremely chilling to Asuna: he is himself responsible for the assault against Laughing Coffin in Aincrad, carried out for the sole purpose of making players morally more upright than assassins, tormenting them in the long run.
This would potentially make PoH the most disgusting character in the episode were it not for the perhaps unexpected but definitely unsolicited return of Sugou, the antagonist of the Fairy Dance story arc responsible for holding a sizable number of SAO survivors hostage to experiment. about them using Alfheim Online as a cover.

Vassago Casals | Sword Art Online Wiki | Fandom

The man is, of course, in prison, but it is in this episode that we discover that Yanai, the assistant who accompanied Higa in his operation to awaken Kirito, is not only the creator of Code: 871 (a funny pun. with his name) who sabotaged the Underworld experiment, but was also Quinella's servant and point of contact, who managed to get all his power and position thanks to him, as well as a very loyal of Sugou himself ( it is also implied that, in order to continue his legacy and not get arrested, he was the colleague who caused Sugou's arrest).

As for Sinon and Leafa, we see the first begin his duel with Subtilizer, Gabriel Miller's alter ego for Gun Gale Online, starting to become familiar with the Incarnation System, transforming his bow into his most faithful (and most practical) Hecate, while the second saves for the broken cap Iskahn and Sheyta, who in the last episode were cornered by the enemy armies.
At this juncture Leafa continues to show her reticence in risking real losses, ordering Lilipin and her orcs to get safe by choosing to do, basically, as a solo tank against the numerous red armies.

Ending with the face-to-face between PoH and the vegetable Kirito, followed by an unexpected signal from the Sword Art Online server, the episode closes its duration with a mostly faithful adaptation, but again an interlude.
This is mainly due to the limited number of pages adapted and the transposition of the conclusion of the corresponding Novel, however this group of episodes, despite the production quality, seems determined to be the most fluctuating and watered down part of the entire narrative arc, with now the third consecutive episode to progress the narrative very little.