I take my hat off to this, not only for the mechanics but also for the simple intrigue behind each level design. From Level 5 onwards each stage has some little "ahaaaa!" or "gatcha!" moment, even if it's as simple as planning out a moderately balanced route for two cars just to see them crash into each other straight away. I did encounter a glitch on level 9, where a clockwise pillar froze and would not move or be deleted. All in all a cracking game, and the mellow and calming soundtrack perfectly balances its, well, balancing gameplay.