In 'Rusty Realms,' players assume the role of a witty code-breaker named Coda, who navigates an abstract universe built from fragmented programming languages and design principles. As the digital chaos unfolds, Coda must solve puzzles and interact with bizarre characters—like the mischievous Bug Goblin and the enigmatic Syntax Witch—while untangling secrets of type-driven design in Rust. The story branches based on choices and players' understanding of coding concepts, leading to multiple endings and encounters.