This seminar examines the transmedia evolution of Astarion, one of the central characters of Baldur's Gate 3, across digital, literary, and audio forms. Focusing on the forthcoming novel Baldur's Gate 3: Astarion by T. Kingfisher and its audiobook narration by Neil Newbon, the project investigates how character identity is preserved and transformed across media. While the video game allows players to participate in the construction of Astarion's narrative through interactive choice, the novel establishes a singular literary version of the character. The audiobook further complicates this transition by restoring the voice of the original performer, creating continuity between game and text. Drawing on adaptation theory, performance studies, and transmedia storytelling, this project argues that Astarion represents a new form of literary character whose identity emerges not from a single text but from the interaction of narrative, performance, and audience participation across media platforms.