Technician 12 is a Space Pirate who was part of the mining base in the Agon Wastes during the events of Metroid Prime 2: Echoes. A scan in the game mentions that 12 fell sick with Phazon Fever and attempted to take control of a deposit of Phazon in the base, holding other Pirates at gunpoint. The scan states that 12 was not killed, but cured of his illness. What ultimately becomes of 12 is unknown.
"Medical Report 07.199.09
Technician 12 relieved after showing symptoms of "Phazon Fever," in where he claimed the Phazon as his own and held us at gunpoint until security arrived."