Their thick exoskeleton provides them with excellent protection, though not absolute immunity, from rifle rounds, allowing them to take quite a beating before finally being killed. With each Arachnid serving a specific military role, the Tanker Bug functions as a form of armor support. The Tanker ejected fuel from a nozzle-like spout in the top of the head. They have evolved the ability to spray a stream of flammable, corrosive liquid from its head. The Tanker Bugs are generally black in color and are nearly as large as Plasma Bugs.