Sword of the Berserk: Guts' Rage, released in Japan as , is a video game for the Sega Dreamcast based on the popular Berserk manga by Kentarō Miura. It takes place anywhere between volumes 22 and volume 23 of the Berserk manga; right after Guts and Puck depart for Elfhelm with Casca, but before Farnese, Serpico and Isidro catch up with them. The music is composed by Susumu Hirasawa, who also composed the anime series' music.
After saving a traveling performer named Rita from bandits, Guts, Casca, and Puck come to a small castle town to rest. Upon arriving, they learn of a disease that transforms its victims into "Mandragorans", making them go berserk, killing people, even their loved ones, without thinking. As the story progresses,the ruler of the castle, Balzac, shows Guts a room in the castle where people infected with the disease are kept. Balzac says he's searching a supposed cure. Guts learns from Balzac that the disease comes from an unusual plant: the Mandragora. It grows underground in a nearby town, and has small arms and legs. It will scream as if in pain when uprooted, killing all who hear it directly.
Balzac asks Guts to retrieve its heart from the Great Tree, and Guts sets off to get it with the idea it can also cure Casca of her madness. On the way, Guts combats the Mandragorans until Nosferatu Zodd arrives. Guts asks him what Griffith's plans are, but Zodd insists on fighting. Guts bests Zodd before Zodd departs and Guts later gets the Mandragora's heart. When he returns to the town, Guts learns the truth; that Balzac only wants to use the heart to become a more "advanced" version of a Mandragoran himself. Guts then proceeds to kill Balzac and ironically, finds the cure back in that same room where Guts was told to get the heart. There, for a brief moment, Casca regains her sanity and is able to speak with Guts about how she had a bad dream before reverting back to her former speechless self.