Asuna has logged into the Underworld using the superuser account of Stacia, the Goddess of Creation. After she descends, she is reunited with Kirito, thanks to Ronie and Tiese. But soon Alice arrives, leading to a precarious situation!.
 s04e01 - In the Far North
        s04e01 - In the Far North
          
        
      
     s04e02 - Raids
        s04e02 - Raids
          
        
      
     s04e03 - The Final Load Test
        s04e03 - The Final Load Test
          
        
      
     s04e04 - Dark Territory
        s04e04 - Dark Territory
          
        
      
     s04e05 - The Night Before Battle
        s04e05 - The Night Before Battle
          
        
      
     s04e06 - Battle of the Knights
        s04e06 - Battle of the Knights
          
        
      
     s04e07 - Stigma of the Disqualified
        s04e07 - Stigma of the Disqualified
          
        
      
     s04e08 - Blood and Life
        s04e08 - Blood and Life
          
        
      
     s04e09 - Sword and Fist
        s04e09 - Sword and Fist
          
        
      
     s04e10 - Stacia, the Goddess of Creation
        s04e10 - Stacia, the Goddess of Creation
          
        
      
     s04e11 - Heartless Choice
        s04e11 - Heartless Choice
          
        
      
     s04e12 - Ray of Light
        s04e12 - Ray of Light
          
        
      
     s04e13 - The War of Underworld
        s04e13 - The War of Underworld
          
        
      
     s04e14 - End to Eternity
        s04e14 - End to Eternity
          
        
      
     s04e15 - Instigation
        s04e15 - Instigation
          
        
      
     s04e16 - Code 871
        s04e16 - Code 871
          
        
      
     s04e17 - Prince of Hell
        s04e17 - Prince of Hell
          
        
      
     s04e18 - Memories
        s04e18 - Memories
          
        
      
     s04e19 - Awakening
        s04e19 - Awakening
          
        
      
     s04e20 - The Night-Sky Blade
        s04e20 - The Night-Sky Blade
          
        
      
     s04e21 - Beyond Time
        s04e21 - Beyond Time
          
        
      
     s04e22 - Alice
        s04e22 - Alice
          
        
      
     s04e23 - New World
        s04e23 - New World
          
        
      
    In the near future, a Virtual Reality Massive Multiplayer Online Role-Playing Game (VRMMORPG) called Sword Art Online has been released where players control their avatars with their bodies using a piece of technology called Nerve Gear. One day, players discover they cannot log out, as the game creator is holding them captive unless they reach the 100th floor of the game's tower and defeat the final boss. However, if they die in the game, they die in real life. Their struggle for survival starts now...