Aliens!
Basket&Ball is back with 10 new levels infested by UFOs and tiny green aliens! They are bent on abducting all circular objects for their evil experiments, so be careful when bouncing nearby! Avoid the bottom part of the UFOs and try to stay out of the alien's sight. It might get dangerously hot! But if you are careful enough, you can use the vehicle for your own locomotion benefit!
The aliens show up starting with level 56, late in the game. These walkthrough videos may help you get there!