According to Rutger Hauer's autobiography, during a break in filming he took a motorcycle ride in the outback. He ended up following a kangaroo for a bit but, then found himself lost in the desert. After a bit of tension he finally he pointed his bike in the right direction and made it back to the set.
The sport played in this movie is referenced in the comic book, "Warriors of Plasm," published in the early 1990s by Defiant Comics. In the comic book, the sport is called Splatterball.
What are the differences between the US R-Rated Version and European Version?
A
The US R-Rated Version misses out nearly 12 minutes of plot sequences that are featured on the European Version of the movie. Additionally an alternate ending can be found in the European Version as well. A detailed comparison between both versions with pictures can be found here.