Sword Art Online Episode 21 English Dubbed Episode Title:The Truth About Alfheim.Episode Description:Kirito and Leafa finally reach Central Arun, the capital of Alfheim, located directly beneath the World Tree. However, an emergency shutdown for server maintenance prompts the two to find a nearby inn and log out. The next day, Suguha accompanies Kazuto to visit Asuna at the hospital. On the way there, he tells her that he will be put in a special school for students who were formerly SAO players to catch up on the school they missed while logged in to SAO. Meanwhile, Asuna stumbles upon a laboratory inside the World Tree, eventually finding the room where experiments are being conducted with the brains of the 300 comatose SAO players trapped in ALO. She attempts to log out of the game by using the gamemaster console inside the room, but is captured by two of Oberon's assistants. However, she manages to snatch a key card before she is thrown back into her cage. Yui informs Kirito and Leafa that Asuna is at the top of the World Tree.