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The Tech 1 Mobile Anti-Air Guns are cheap mobile low- end AA defense. They do not have a very high DPS, but are very cheap and can easily be built in large numbers.
[edit] Factional differences
The four Tech 1 Mobile Anti-Air Guns are the UEF Archer, the Cybran Sky Slammer, the Aeon Thistle and the Seraphim Ia-istle. These unit all have the same cost, health, range, weapon muzzle velocity, and about the same damage per second. The things that set them apart are different rates of fire, number of shots per salvo, and projectile damage (among other things). The Cybran Sky Slammer's Nanodart Launcher has the ability to fire at and track both land and air units. This ability makes it the most versatile of the T1 mobile AA units.
It should be noted that the Sky Slammer's darts have a slower speed-up than most AA missiles, and thus are slightly less effective against aircraft than the other factions' T1 mobile AA units. This is counterbalanced by the fact that the darts are guided and can be switched to attack ground units, however in ground attack mode they lose the tracking ability.
Seraphim T1 Mobile Anti-Air Bot awaiting orders