Giant Walking Machines
Syd Mead didn't work on The Empire Strikes Back, but he made a significant contribution nonetheless, when his designs for US Steel ended up informing the imperial walkers deployed on Hoth.
Riders astride giant lizards might not have been an entirely novel concept by the mid 70s, but Ron Cobb's take on it had an air of the fantastic, while being grounded in reality. Cobb would go on to work on creatures for Star Wars , and this early design probably inspired the Dewback.