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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 are available as a special anti-infantry unit in StarCraft II: Wings of Liberty at the cost of 15 zerg research points and access to the Hercules dropship. They 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.
The Predator unleashes a deadly field of electricity each time it attacks. Deals 20 damage.