You do not need to be an Asuna fan (as I am) to acknowledge that she has been woefully underused and underdeveloped through the first five story arcs of the SAO franchise (including Extra Edition). Despite being one of the original two faces of the franchise, she has spent much of her time absent, limited, shuffled into secondary or mere ensemble status, or only viewed in terms of Kirito. In fact, one of the very few times we get much insight into who she actually is (rather than how she interacts with Kirito) comes in one of her earliest appearances, during the conversation she has with Kirito back in episode 2 of the first series about how she's resolved to stay true to herself no matter what happens. And too rarely since that episode's boss fight has the strength which made her one of SAO's leading players truly shown through. Mother's Rosario, the final animated arc of the franchise to date, changes that, and in a big way. That is one of the major reasons why it is also the best and most satisfying story that the animated side of the franchise has to offer.

Relegating Kirito to a supportive secondary role and making Asuna the focal point character for most of the arc transforms the series, allowing viewers to get vastly deeper insight into Asuna's character and background than we have ever had before. For instance, we learn early on that, unlike for most other players, getting back to her family was never a factor in Asuna's struggle to survive SAO. The arc's second episode shows all-too-clearly why: her mother is a classic helicopter parent, and as a result their relationship is strained at best. Director Tomohiko Ito emphasizes the contrast between Asuna's comfort with the virtual world and discomfort with her home life by showing Asuna exiting from the warmth and hominess of her virtual cabin to a real-world bedroom where the temperature is set to only 15° C (59° F). Not really chilled enough for one's breath to show, but that still adds symbolic weight to how cold Asuna finds this side of her life.

Thankfully, the creative and production stuff avoid demonizing the mother. She simply does not understand her daughter or her daughter's world, and Asuna bears part of the blame for that because she has never really had a frank heart-to-heart talk with her mother. Symptomatic of this is one telling scene where Asuna, rather than trying to explain herself, just walks away from her mother's demands and drops a vicious snipe in the process. For all the power that she had in SAO, for all of that iron will and determination, Asuna is powerless in the real world, and it frustrates her every bit as much as it did Shino that she cannot transfer her game power into her real life. (In fact, this is the predominant recurring theme in the entire franchise.) So what is the best way for a character to overcome circumstances like that? Have someone else show them the way. And that it where Yuuki comes into the picture.

Even considered solely on her own merits, Yuuki is a wonderful addition to the cast. Her spirit and vivacity are unmatched by any other character in the franchise; in fact, no one else even comes remotely close. Her energy is infectious, her charm is undeniable, and her grit is second to none. (The presence and importance of the latter will not be apparent at first, however.) She is immensely strong but without the “broken” feel that Kirito can give off and (also unlike Kirito/Kazuto) has personality to spare. She also makes practically the ideal match for Asuna as a co-star because their pairing allows Asuna to be the mature older sister and yet still learn from Yuuki's example. In fact, some of the arc's best scenes involve the two of them talking like sisters or best friends.

The story structure of this arc also sets it apart from previous ones. Whereas all of the other arcs – in one sense or another – come down to a climactic battle or battles, in this one the boss monster battle which is the Sleeping Knights' goal is merely the halfway point. The remaining three and a half episodes deal with the secrets of Yuuki and the Sleeping Knights and the impact learning about them has on Asuna. That is where the juiciest meat of the story lies.

Spoiler Alert (from this point on)

The SAO franchise has always pushed that notion that staying alive means little if you aren't actually living. This takes many forms in the Aincard arc, is a major underlying theme in the GGO arc, and is present in smaller, subtler doses in the Fairy Dance arc. It defines Mother's Rosario more than any of the others because Yuuki is the very embodiment of that notion. Her situation is so awful (some would say to an improbable extreme) that she could easily be one of anime's ultimate tragic heroines, but that's not who she is – not even for a second. She fights an unwinnable battle against an implacable foe but does so gloriously, with her one flaw being that she is hesitant to trust the emotional resilience of those who might be dear friends, even if only for a short time. And she definitely underestimates Asuna in that regard, for just as she inspires Asuna towards dealing with her own problems, so, too, does Asuna show Yuuki things that she might have otherwise only dreamed possible. That makes the last two episodes a thing of beauty as the simple but powerful moments stack up, including a Yuuki-prompted resolution between Asuna and her mother. As a result, when the inevitable climax comes, it carries a satisfying emotional impact, especially on repeat viewings. (And while certain aspects of that scene may seem overblown, events happening in the real world at the exact same time that episode 24 originally aired showed that they are not necessarily exaggerated. Look up Codex Vahlda after watching the episode to understand the full extent of possibly the most eerie anime-related coincidence ever.) Few characters leave the stage as gracefully as Yuuki does.

The last three episodes also introduce the arc's other most intriguing aspect: the Medicuboid, which is a full-dive VR rig designed specifically for medical use. Technology which allows patients who are otherwise invalids to be remotely active has been used in several earlier sci fi anime series (in fact, direct predecessor series .hack//SIGN used a much more limited version of this), but to my recollection never before has its applications as a medical tool been so specifically and thoroughly explored. The realistic possibilities it offers, especially for terminal care, are breathtaking and visionary, especially when combined with the camera technology that Kazuto was shown developing for Yui at the end of the previous arc.

The arc would not have achieved its full impact in English without some truly outstanding vocal efforts. Cherami Leigh, the voice of Asuna, does her best work of the franchise throughout these episodes, Robbie Daymond (the voice of Tuxedo Mask in the recent dubs of Sailor Moon) is a great fit in a small but important role as Dr. Kurahashi, and all of the other supporting roles are solid, but Erica Mendez, as Yuuki, shines brightest. She has done some other recent great work (Fu in Yuki Yuna Is a Hero, Diane in The Seven Deadly Sins), but here she perfectly captures the essence of who Yuuki is as a person, including all of the tricky emotions which go with her later scenes and a reasonable adaptation of the tomboyish speech patterns Yuuki had in Japanese. She owns the role so thoroughly that I cannot imagine anyone else doing it equal justice in English, which led to me making it my Best Female Vocal Performance pick for 2015. The English script does take quite a few liberties through these episodes but none that struck me as game-changers; its only real flaw is its awkward handling of how Zeeken's gender is initially disguised, but that was an impossible feat anyway given how differently gendered pronouns work between Japanese and English.

Technical merits are more typical by series standards. The only thing comparatively special about the backgrounds are some snow-covered landscapes, and the only battle scene not hampered by normal animation shortcuts is Asuna's well-articulated duel with Yuuki, though that does not keep some of the other fights from still looking pretty cool. The occasional off-model flaws which have always plagued the character animation are also still evident, but so is some wonderful use of color; this is especially evident in the arc's climactic scene. Amongst new character designs, the only ones which stand out are younger versions of Asuna and various versions of Yuuki; as cool as her ALO avatar looks, her real-world character design is startlingly more impactful. (Anime titles which have the guts to do that are extremely rare.) Also watch for some nice subtle touches and perspective shots involving the virtual version of Yuuki when she's not in her ALO avatar. Unlike previous arcs, this one entirely lacks anything which could fairly be called prurient fan service.

The musical effort it as strong as ever. In this arc the musical score actually stands out the most in supporting its more sensitive non-battle scenes, such as Asuna's first confrontation with her mother or just about any scene in the last two episodes. Opener “courage,” from the last arc, gets a visual update so packed with subtle hints about the arc's content that its visual choices can only be fully appreciated after seeing the arc to completion. It also lyrically fits much better with this arc than the Calibur arc. Insert song “Separate Way,” which replaces the opener for the final episode, is also a beautiful and meaningful fit. Powerful, moody new closer “Shirshi” by LiSA, which almost exclusively features Asuna and Yuuki, makes a great cap for both the episodes and the arc in general; watch for slightly altered visuals for the final episode.

As with previous releases, Aniplex has packed this one with Extras in an effort to justify the high price. Both Blu-Rays include the usual assortment of Web Episode Previews, clean versions of the current opener and closer, and three installments of “Sword Art Offline 2,” which are as funny as ever and highly recommended. This block of episodes includes four (subtitled) Japanese audio commentaries, for episodes 19, 21, 23, and 24, featuring varying mixes of voice actors, production personnel, and original author Reki Kawahara. All of them are actually pretty insightful, especially concerning decisions made about how to voice certain parts, and may help viewers pick up on details that they otherwise would have missed. Most significant is one comment Kawahara makes near the end of episode 24 concerning Akihiko Kayaba, which clarifies that one late revelation was never intended to soften Kayaba's status as a villain; it was instead intended to demonstrate that neither the main characters nor the viewers yet understands the full nature of Kayaba's original ambitions. The English ADR Director and voice actors get their turn on the bonus disk, which holds all 63 minutes of “Sword Art Online – Radio USA – Part 3.” The most interesting revelations there are that, like with the Japanese cast, tears flowed freely during the dubbing for the final episode and some unusual methods were used to make the climax sound exactly right. Physical Extras include a Weis Schwartz card featuring Asuna and Yuuki, a trio of postcards, and a booklet containing episode synopses, character profiles, and images of assorted settings; the cover is a wrap-around map of floor 24. The back of the bonus disk's case also has a complete listing of the Monument of Swordsmen as shown in episode 21. Everything also comes in the standard sturdy artbox and, as before, Spanish subtitles are among the options.

Since Kirito often stands at the heart of complaints about the SAO franchise, is him only having a minor presence here the key factor to this arc's success? Actually, yes. For all of his cool factor and screen time, Kirito still has one of the franchise's weakest personalities, and that has long been a drag on the series. Freed from the lodestone, the character development excels. He never could have meshed with Yuuki the way Asuna does, either, and the GGO arc showed that he cannot convincingly capture the mix of vulnerability and strength necessary for this arc. Hence stepping away from the long-time main protagonist is actually what allows the series to finish on its strongest possible note.