Just wanted to put a message out here. This competition is a unique one for us and is obviously more restrictive than our usual jams that we host. But as a result of this, these types of jams are much less competitive. That means if you participate and create some kind of game that meets the requirements, you have a pretty good chance of winning.
You can come check out one of the games on our server in the jam-devlogs. He is using UModeler X to make very simple 3D models. Nothing complex is needed; you can certainly get by with just basic modeling of rectangles, cyclinders, spheres, and maybe a combination of all of them. Try it out and you might be surprised with the results.