Two radically different factions have set up camp on the island and are fighting each other for control over territory and the spoils found upon the land. Even worse, monsters and other strange incidents are popping up all over the island, making this a very treacherous place to explore.
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The game, which designers Wizardbox and Piranha Bytes have spent more than two and a half years working on in tandem, has been designed to create a true living world where everything reacts to your actions. For instance, I was told that a player could save a young woman close to the start of the game, and she'll become a companion and aid you with your moves. If you choose to leave her alone, or take her and abandon her later on, the character, and the reactions from other NPCs in the world, will respond to your personal decisions, denying you aid or even attacking you outright.
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Players will need to individually choose at some point what side they'd like to eventually belong to and will find that the game will change based on that decision. In fact, the designers mentioned that they're aiming for at least sixty hours of play for each faction, meaning that there will be a large amount of replayability for players to check out within the game​

Although the game was being demonstrated on a PC, I was told that the lead platform for Risen is actually the 360, and that the developers have been spending a large amount of time working on the fight system and the other basic mechanics to ensure that the game works well on both platforms.​