Geon is a mostly linear turn-based JRPG with a setting that has many sci-fi/fantasy elements while also taking place in a not so distant future ruled by a ruthless despot only known as "George".
Play as a young man who is about to complete the final test before he becomes a member of society. After (inevitably) failing you're forced to leave your home and travel out into the world unsure of where fate may bring you, thus begins your journey. Along your journey you are faced with the task of meeting George, acquiring various party members, and fighting many foes from beyond this world in order to save it from destruction, one of whom might not be who they appear to be...
The game-play is mainly focused on turn-based combat where you can fight many different types of enemies and use many different moves and weapons, many of which have various unique effects and types. For example, there are the gun type weapons that attack multiple times but have a higher chance to miss; the game-play also has many puzzle and exploration elements that involve mini-games and talking to certain NPCs. The game has a heavy emphasis on story/dialogue and focuses on various topics and ideas in humorous, serious, and even surreal ways, you also gain multiple party members throughout the game who have different personalities and join/leave your party at certain points in the story. Additionally there are many secrets, mysteries, side areas/dungeons, and people to talk to, so it's usually best to search the many areas that this world has to offer in order to progress and find things you wouldn't otherwise.
