Hard Ball is a cousin to chess, soccer and football, but a very different one. Best played with someone, but still enjoyable to fiddle around by yourself to discover the deeper mechanics and then definitely invite someone to play along.
It is still in development, but also it is feature complete. Everything from this point on will be about adding visual improvements.
There is a small issue on how the goals are designed right now that created some confusion with a small batch of play-testers (some friends of mine, lol), this is possibly the only thing that will change to improve the experience.
I'd be glad to discuss anything related to the game because there is so much under the hood ;)