Lex is the explosive expert among the Spartans. She can shape a charge to cut into a single steel bolt with only a whisper of sound, or rig a hundred thousand liters of kerosene to blow into a 'firestorm from hell'. Ironically, her temper is well known as ticking time bomb.Ol-222 was conscripted into the Spartan-III program in 2517 when she was singled out as a physically and intellectually superior child by Dr. Catherine Halsey. She was abducted from her home and replaced with a Flash Clone, then sent to Reach where she was trained with the rest of the Spartans by Chief Petty Officer Mendez and Deja. She participated in numerous Spartan training missions to Emerald Cove, Chiron, Military Reservation 01478-B, Military Wilderness Training Preserve, and several in the Highland Mountains.
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