Thanks for playing the game! The difficulties were really hard to figure out (and I kinda failed to do something really interesting for them) because I wanted to change the camera speed and other parameters, but the way I coded stuff made that only one thing could be changed for each level. And it was the " error multiplier", that changes how much things weighted for the error calculation. Next time, if I do an arcade game, I'll try to make each mode really stand out!