I got this idea from the TU Indiegogo page mentioning lava as an obstacle in Ball Race:
So, I was thinking it’d be really cool to have a volcano level in Ball Race. The background would be a tropical island with volcanoes all around it, and a huge volcano in the center. Here’s a quick sketch I made to show how it could look:
The levels would be semi-close to the ground, and would have rocks falling from the volcanoes onto them. You would also have to avoid eruptions. The final level would have you falling into the mouth of the giant volcano in the center.