It’s pure nostalgia. The callback to Aincrad, the return of “Sword Skill” callouts, the music swelling – it’s designed to make long-time fans cheer. And it works, emotionally. Kirito’s PTSD from losing Eugeo mirrors his trauma from Sachi and the Moonlit Black Cats. He needs to remember he fights with others, not just for them.
Following the battle with Administrator, Kirito is left in a catatonic state due to a power surge that damaged his "fluctlight" (soul) while communicating with the real world. Alice, now an Integrity Knight who has regained her free will, takes him back to her hometown to care for him in seclusion. However, peace is short-lived as the Final Load Test The Conflict sword art online alicization war of underworld link
The real-world sequences with Rinko, Higa, and Kikuoka finally get room to breathe. Higa’s moral dilemma (should he copy Kirito’s fluctlight to save Underworld?) is one of the series’ best ethical questions. It links back to Alicization ’s opening discussion of artificial souls – do copies have rights? It’s pure nostalgia
Sword Art Online: Alicization - War of Underworld serves as the explosive finale to the massive Alicization arc, spanning the second half of the season Kirito’s PTSD from losing Eugeo mirrors his trauma
The emotional climax of War of Underworld occurs when Yui, Lisbeth, and Silica bridge the gap between multiple gaming platforms. They establish an unprecedented digital link, allowing standard VRMMO players from ALfheim Online (ALO) and Gun Gale Online (GGO) to transfer their personal avatars directly into the Underworld.