Once again a theme which is a bit odd and caught my interest:
Only blocks placed directly on the ground (or in the ground for some blocks) are allowed.
As someone pointed out that it would be tough to get a fullspeeder done without wallrides and turnovers I tried my best to do just that.
The biggest challenge for me became making that flat map as interesting as possible without repeating patterns.
Unfortunately I really didn't get as far as I would have liked. You gain pretty much speed and turns are getting difficult, but I hope it's still a decent map.