ME-ORT-61 "Gigapede" Off Road Train
It is quite clear that a means of shipping supplies, munitions, and troops in vast quantities is required. For these tasks, trains are quite clearly ideal. However, railways are distinctly vulnerable to airstrikes and other attacks damaging and destroying the tracks. The solution therefore, is to make a train that can go wherever it damn well pleases, regardless of if there's rails there or not.
Enter the Gigapede system, the world's first train designed for off-road driving. The engine vaguely resembles a standard diesel-electric locomotive, but the rear wheels have been replaced with a pair of long tank treads, with two relatively normal wheels in the front for steering. The GOFAST-burning engine provides these treads with plenty of power to drag whatever load the Gigapede is currently hauling. The Gigapede is designed to be able to haul up to 250 tons of load up a 30% grade, ensuring that it can provide plenty of logistical support wherever needed. Notably, the engine can be easily armed as it has a mounting point on the front suitable for a vehicular ICE thrower or autocannon mount.
Cars the Gigapede can haul include standard cargo or passenger cars (modified with heavy duty off-road tires), or any number of military modules. This includes mobile command centers, a field artillery battery mounting the Bumblebee guns from our Navy, Penguin missile siloes, autocannon AA mounts, and ICE thrower broadsides among other possibilities. Each armed car is designed to be as self-contained as possible, so that if the engine is destroyed they can still shoot back.
All in all, the Gigapede promises to not only greatly assist with Mereth's supply situation, but also to deliver heavy firepower where it is needed.