Sky-1 is the name given to the physical embodiment of Skynet and appeared as a large, bipedal machine. It contained a variety of weaponry built into its body allowing it to combat opponents in addition to holding a portion of Skynet's intelligence.
In 2032, Superman and a Steel from the future encountered Sky-1 in one of the Terminator production plants where they battled against it. However, despite their super-powered nature, Sky-1 had been prepared and made use of synthetic Kryptonite as a weapon against the Man of Steel. Capturing the two, Sky-1 attempted to download information from their minds in order to hasten the creation of the Omega Point and thus allow the machines to dominate the Earth. During the download process, Steel managed to free himself and later Superman where the Kryptonian used his heat vision to down Sky-1. However, even crippled, he continued talking about the imminent Machine's victory, and his words gave Superman an idea about how to defeat the machines once for all: create a human "Omega point", which allowed the Resistance to finally destroy all the machines.