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Predators, sometimes called "cybercats", are big, heavy robots shaped like cats.
Some were owned by the Screaming Skulls, and were used in an attempt to kill their former captives, War Pig members Vin Iggins and Cole Hickson. One knocked Iggins down, but Hickson terminated them with shots from a pistol.
Predators unleash a lightning field AoE burst which deals 20 damage with every attack. While they gain no bonus against any unit type, a handful of them can easily bring down swarms of zerglings or other low health units with their AoE burst attack.
A primary weakness to using predators is that, for their cost, they are not very durable for a melee unit. Also, because they are mechanical units, they cannot be paired with medics or medivac dropships (though they can potentially be paired with the science vessel). Without armor upgrades, predators will die fairly easily against ranged attackers, especially those that deal bonus damage to armored targets.
Predators are strong against zerglings, banelings, infested terrans, marines, firebats, reapers, hellions, and occasionally zealots and sentries. Unfortunately, they have many counters: marauders, siege tanks, thors, diamondbacks, stalkers, immortals, colossi, roaches, hydralisks, ultralisks, and any air units. This makes the predator an extremely specialized unit.
The Predator unleashes a deadly field of electricity each time it attacks. Deals 20 damage.