Factual error: When Grace is fighting the controls of the C-5 cargo aircraft there is a shot of part of the instrument panel. Among the items on the panel is a switch labeled "tail rotor quadrant." The C-5 does not have a tail rotor. Helicopters do. (01:35:00)
Factual error: When Grace first shoots the Rev-9 Terminator, she is using a Winchester Pump Shotgun with a long magazine tube. She however fires 13 rounds at the Terminator, while the shotgun is only able to hold a maximum of between 7-8 shells in the magazine tube.
Answer: Skynet and Legion were both developed for identical purposes: defense network artificial intelligence. It stands to reason they would both evolve in similar ways. Since both Skynet and Legion were fighting a similar human resistance, they both developed similar infiltration units.
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