He wanted the truck to be more monster-trucky.

My son Jack likes monster trucks. One afternoon he found out we could make a game together, and after that there was no other plan.

He supplied the direction: more trucks, bigger jumps, more monster-trucky. I did the typing. Then I watched what he actually played, not what I thought he would play, and we changed it again.

We found the build. It has four tracks, five trucks, three rivals, jumps, boosts, power-ups, and exactly the amount of mayhem he asked for.