I love it so much! The waiting Sisyphus push for the boulder to reach the top is hilarious, as if saying, "Phew, I'm awesome!" Even funnier is pressing X to make the boulder roll again, and Sisyphus initially maintains the previous action, then runs down in panic while raising his hands! Hahaha!
Also, the score and difficulty are directly proportional. The boulder is easy to roll down at the bottom, but at the top, you need to hit the keyboard vigorously, and the score is higher as well! I really love this game!