I can't stop thinking about applied fun theory to card game mechanics. I'm building a card game where you never leave the flow state. (I know there's been a lot

I can't stop thinking about applied fun theory to card game mechanics. I'm building a card game where you never leave the flow state. (I know there's been a lot of cash grab card games recently. I just genuinely enjoy card games.) Specifically this question - Why is soccer more widely played than checkers? Physical Mastery - repetitive exploration of real world ball physics encourages a sense of mastery. Checkers doesn't have this. I've built a physics sim into the card game to replicate this sense of building mastery through exploring the physics system to win. Mental Mastery - Both soccer players and checker players make choices that feel fun and meaningful. When trying to dribble around an opponent, they have multiple options they must chose (right or left, fakeout). The player must have a model of what their opponent might do and react based on that. Updating their model is a sense of mental mastery that can be rewarding and contribute to flow. Real Time - Soccer doesn't have turns. In checkers, waiting for the opponent can break the flow state if you already know your move. The demo allows players to play cards in real time. The catch is - when you run out of cards in hand you loose. Accessibility - People can just pick up a ball shaped object and ball. I built a demo in WebGL so people can just hop in. Simplicity of Rules and Depth of Choices - Instead of having a convoluted health system, the amount of cards in your hand are your health. This makes picking up the game easy, there's just one rule to keep in mind. This allows for a variety of fun choices because each card you play lowers your health. This creates a fun risk reward system with no additional rules. The other idea is to use the existing physics system that players are already familiar with. That way there's no tutorial - players already know how cards handle and drop in real life.