"Etrian Odyssey" is a series of role-playing video games developed by Atlus. Set in a fantasy world, players create a party of adventurers to explore a vast, mysterious labyrinth known as the Yggdrasil Labyrinth. The gameplay focuses on turn-based combat, dungeon crawling, and map-making, allowing players to chart their progress as they delve deeper into the labyrinth's challenges. The series is known for its challenging difficulty and strategic gameplay, requiring players to carefully manage resources and party composition. Each installment introduces new classes, monsters, and storylines, while maintaining the core mechanics that have made the franchise popular among fans of traditional RPGs.