Mallus is the main antagonist in the third season of the Arrowverse series, DC's Legends of Tomorrow. He is a powerful, evil and ancient time demon who was sealed inside another dimension due to his fearsome presence and desire to wreak havoc throughout all of time, who now returns to claim vengeance for his long imprisonment.
He is voiced by John Noble, who also voiced Unicron in Transformers: Prime, Walternate in Fringe, Henry Parrish in Sleepy Hollow and Scarecrow in Batman: Arkham Knight. While possessing Nora Darhk and Sara Lance, he is portrayed by Courtney Ford and Caity Lotz.