Sword Art Online returns to our screens with a new season as announced at the "Dengeki Bunko Aki no Saiten 2017" (Dengeki Bunko Fall Festival 2017) event in Tokyo. Specifically, the new TV anime will be an adaptation of the Alicization arc of Reki Kawahara's Sword Art Online Online light novel and will be titled Sword Art Online: Alicization.

The first trailer of the new season: 

The protagonists of the series return to the original roles with Yoshitsugu Matsuoka as Kirito and Haruka Tomatsu as Asuna. In addition, Ai Kayano gives her voice to Alice and Nobunaga Shimazaki will play Eugeo. 

During the "Dengeki Bunko Aki no Saiten 2017" event, it was also revealed that Keiichi Sigsawa’s spinoff novel titled Sword Art Online Alternative Gun Gale Online will also get an anime adaptation. The anime project will feature Tomori Kusunoki and Yōko Hikasa as Llenn and Pitohui respectively.

Sword Art Online counts two television series, an anime special and a film titled Sword Art Online: Ordinal Scale, which premiered on February 18. Moreover, multiple manga series, games, and a virtual reality demonstration in Japan have been based on the novel.

Source: animenewsnetwork.com