Psychologist Mihaly Csikszentmihalyi found that motivation and engagement peak in a narrow "flow channel" where a task's challenge closely matches a learner's current skill — too hard and anxiety takes over, too easy and boredom sets in. This simulator renders that relationship as a real 3D landscape: challenge and skill form the ground plane, and the height at every point is a motivation index computed from a Gaussian function of their log-ratio. A learner marker climbs the terrain as practice grows skill over time, fastest while inside the flow ridge and stalling in the anxiety or boredom zones on either side. Tune the task's challenge, the practice rate, and how forgiving the flow channel is to see how adaptive difficulty keeps engagement — and skill growth — compounding.