Maybe you remember this post (from over a year ago) in which I showed a very primitive version of a little magnet car which at that time I got into action by moving my hand holding a magnet under the road plates.
Now I got a step further as you can see in the next video. This time a lot of Technic Chain Tread 38 (#57518) parts are being used and some Technic Chain Tread Wheels (#57520) and of course the magnetic magic is still performed by these parts: Magnet Cylindricals (#73092)
Unfortunately it is a very unreliable construction. I was glad to get it on video in one take, because a lot of times the vehicle just stops while the underlying magnet set moves on. The heavier the vehicle gets of course, the harder it is to get this contraption to work. I am afraid I need a whole new idea for some next LEGO WORLD GBC 😦