Chapter 4 rounds out this study with an adaptation that that is simultaneously more conventional (being a graphically vivid first-person video game) and more confounding (being based on Henry David Thoreau’s nonfictional Walden) to typical notions of immersion, players, and play. I draw on Janet Murray’s concept of “immersion” and Alenda Y. Chang’s metaphor of the “mesocosm” to frame the experience of Tracy Fullerton’s Walden, a game as one of being incorporated into a system which includes the gameworld, the real world, and the knowledge and beliefs of the user themselves – a framing encouraged by its minimalist mechanics and graphical realism. While they cannot recreate Thoreau’s experience in the actual woods (nor could that be possible), the open-ended wanderings within the virtual woods allow for an interpretatively productive sense of play that lies at the heart of not only all game adaptations, but all texts. After interrogating the seemingly contradictory ways that play is theorized within both Walden, a game and Walden the book, the chapter ends with an examination of what literary game adaptations can teach us about being “at play” not just within the realm of literature, but within the world at large.