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Intro. Dr. Halsey simultaneously deploys two Ultimate Spartans in different galaxies. John-117 with Cortana defends humanity. S-127 with Kalliope acts in a foreign galaxy for secret missions and survival. They never crossed paths. Each AI is programmed differently to test two philosophies of war: 117 = emotion and humanity, 127 = efficiency and survival. The two represent the pinnacle of the Spartan-II program but follow parallel paths that will eventually intersect, revealing their differences and forcing a decisive clash or alliance.

Nyx - Spartan-127

@Obsidian_Fox