Departure
Kirito and Eugeo realize Selka has taken off to the End Mountains alone, and decide to chase after her. As they enter the cave, they encounter goblins, presumably from the Dark Territory, and must engage in a battle.
Aired 28/10/2018EP 4 - Departure
Sword Art Online: Alicization
Kirito awakens in a vast, fantastical forest filled with towering trees. In his search for clues to the truth of his surroundings, he encounters a young boy who seems to know him. He ought to be a simple NPC, but the depth of his emotions seem no different than a human. As they search for the boy's parents, Kirito finds a peculiar memory returning to him. A memory from his own childhood, of this boy and a girl, too, with golden hair, and a name he should have never forgotten - Alice.
(Source: Yen Press)
Note: The first episode aired with a runtime of ~48 minutes as opposed to the standard 24 minute long episode.