First Test Design
Initially, it was planned to portrait the Grievers as large, robotic machines in the film. However, prior to being hired for the job, I had already developed a test design that incorporated the hybrid creature concept from the novel. I presented this design to director Wes Ball, who was immediately drawn to it. Together, we made several adjustments to make them more intimidating, such as adding a scorpion-like tail. Slugs and coconut crabs were big influences for me in finding the overall body shape. The head is a mixture of caterpillars, bulldogs and piranhas.
Light Dots
Since we see the Grievers mostly in the dark, Wes wanted to find a way to illuminate them with some kind of 'light dots' and sensors. This is one of a few options that I sent to him. One idea was to put these lights underneath the slightly translucent skin which would constantly move in one direction.
Early Beetle Blade variations
The Beetle Blades didn't end up in the film, but I had a blast working on them. There were a few fun scenes in the script. Wes described them as the 'observation cameras' from the maze, therefore I attempted to make the design very functional. At the very beginning we thought about making them bio-mechanical, similar to the Grievers. Wes wanted something like a mutated and scary looking sowbug.