A compulsion loop or a core loop is a habitual, designed chain of activities that will be repeated to gain a neurochemical reward such as the release of dopamine. Compulsion loops are deliberately used in video game design as an extrinsic motivation for players, but may also result from other activities that unintentionally create such loops. In game design Compulsion loops can be used as a replacement for game content, especially in grinding and freemium game experience models. The opposite of rewarding predictable, tedious and repetitive tasks are reward action contingency based systems, where players overcome game challenges with clear signals of progress.Players perform an action, are rewarded, another possibility opens and the cycle repeats. The positive reinforcement effect can be strengthened by adding a variable ratio schedule, where each response has a chance of producing a reward. Another strategy is an avoidance schedule, where the players work to postpone a negative consequence.A well-known example of a compulsion loop in video games is the Monster Hunter series by Capcom. Players take...