Cool, Rampage always looks sick. Thanks. So Iooks like ILM never made promotional renders of Jolt for Hasbro. That's a mad bummer. Early brains, seen that before I think.
Brains was originally gonna be human sized, and that was used in a few comics(though with a design much further from the final product than this one). So in this stage of production he probably turned into a small wheeled...thing. I don't know.