Tales of Berseria is a role-playing video game, where players navigate the game's world through the game's characters from a third-person perspective. As with previous Tales games, characters can interact through Skits, animated clips that play outside cutscenes and battle: characters are represented by head-and-shoulder portraits, and conversations can range from serious to comedic. New to the series' Skit systems is a cut-in effect, where at certain moments within skits characters in various poses will appear in response to the dialogue.
Berseria takes places in the Holy Midgand Empire, a powerful country that rules over this world's archipelago of a continent. The game's world is shared with Tales of Zestiria, although the events occur before the latter. There are countless numbers of islands around, and Midgand's rule crosses even the seas. Areas of land and islands in the game are divided into "territories." When she was a child, Velvet Crowe and her younger brother Laphicet were saved by her brother-in-law Artorius when a Scarlet Night happened and daemons attacked their village; Velvet's pregnant older sister Celica was killed during the event known as the "Opening". Seven years later, Velvet takes care of her sickly brother with Artorius. The Scarlet Night returns, with the entire village succumbing to the Daemonblight: when Velvet finds Artorius, she sees him sacrifice her brother as part of a ritual, known as the "Advent". Artorius attempts to use her for the Advent as well, but she fights back and the Daemonblight possesses her arm, mutating it and turning her into a Daemon called a "Therion", with the ability to absorb Daemons. After three years in prison, Velvet is freed by Seres, Artorius' former malak, who has broken away from him. During her escape, Velvet aids fellow prisoners Rokurou and Magilou and fights against the Praetor Exorcist Oscar Dragonia. Seres takes a fatal attack when Oscar turns one of his Malakhim servants into a dragon to face them. Absorbing Seres at her own request, Velvet makes a final attack on Oscar that blinds him in one eye before he escapes. Velvet realizes at this point that Seres must be a reincarnation of her deceased sister, Celica.