Allied low tech "hobo-flak". An m113 with a vulcan minigun is the principal allied linebacker. It is flexible and pretty cheap. It has a long range, but at the fringes of its reach, expect massive inaccuracy. It can target its vicious gun against ground units, but with a severely reduced range (due to land features mostly not represented in RA like rolling ground and such). It is not a very effective against tanks, but can in a difficult situation be fired at infantry and light vehicles. But again, its not best suited for such roles.
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Allied stealth bomber. It is invisible like CNC stealth tank. It has to fly over the enemy target in order to engage it and when it drops its bomb, it is visible to the enemy. It can also be detected by AA turrets and interceptors at close ranges. Dunno about whether the shadow is visible to the enemy.
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I have also charted out some game features.
Armor groups. Rather than the normal RA heavy, light, none and concrete armor types, I am expanding this a bit.
Ground armor types
MBT-type. This is the pinnacle armor type: MBT armor is often very heavy and composite with various materials in addition to steel like depleted uranium to add protection. MBT armor type includes T-80, allied MBT, allied super tank and possibly the ore miner. mbt type is virtually impervious to small arms fire, light rockets, etc-
Heavy-type. This armor type is for vehicles reasonably heavily armored with steel, i.e. med tank, T-72, BTR, BMP, etc.
Light-type. This type is for "soft-skinned" vehicles like jeeps, humvees, bdrms, trucks and so forth. These vehicles do not have much steel or other armor.
Concrete. This type includes most base buildings and defense structures including walls.
Earth. This type includes sandbags, hesco walls, hesco towers, pillboxes and some soviet buildings I have planned.
Air armor types.
Light. F-15, stealth bombers and migs and others fall under this group.
Heavy. Flying bathtubs like A10 fall into this group. They are not very vulnerable to cannon fire and missiles are required to have any reasonable effect on this armor type.