After a GLA task force was decimated by advanced USA melee weaponry, the GLA decided they needed melee vehicles of their own. A GLA commander tore down several of those statues of crossed swords coming from the ground, and had them bolted to Scorpion tank turrets. This was the result:
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This is the GLA Swordion tank. Swinging their massive Scimitars horizontally, they can cut down massive swathes of enemy troops in front of them. They excel at anti-infantry, due to the devastating power of the giant sword against infantry, and the new supercharged engines for Swordion tanks. However, they do not gain the Scorpion rocket like the normal tanks, as they can't be used effectively. The turret must point backwards to minimize the Swordion's profile when moving, as otherwise it would bump into structures, accidentally clothesline friendly infantry, and other negative side-effects.
The only way to cram this into a GLA Arms Dealer is to make a Melee Vehicle commandset like USA. This might be a good option, as it also would allow for other melee vehicles in the future. Also, it would make melee vehicles a basic faction exclusive, while the generals have a variety of specialized weapons instead. The melee vehicle commandset button can just replace the pointless SetRallyPoint button, which does nothing as clicking when you have the building selected does that anyways.
Basic cost and build time will be the same as that of a normal Scorpion tank.
-Jordan