"Even though maintaining the Cleanser was my main directive for over a hundred millennia, protocol stated that I do whatever it takes to protect the device from falling into the wrong hands. As was the case when I was forced to destroy the objective I was supposed to protect. But it had the desired outcome to stop those who wished to use it for their own gain."
―589 Curious Puzzle
589 Curious Puzzle is a Forerunner Ancilla that formerly served as the monitor of a Forerunner doomsday device designated the Cleanser. It was created by a Builder with the title of the Carpenter. After lying dormant with its intelligence stored directly inside the Composer, Puzzle was awakened by Covenant pirates under command of Grono 'Yendam. Finding out their attempts to use the Cleanser against the Reclaimers, Puzzle directed the Cleanser to lock-down, Creating an energy shield that saved Spartan Benjamin Nishurd when he destroyed the ship it was on. Years later, the Created would find a partial remnant of Puzzle's core and store it inside of an Ancilla shell, thus bringing the AI back. Puzzle would eventually deduce that since the Created wanted the Mantle for themselves, and that humanity had created them, the Reclaimers were to fault. With this, the partially rampant Ancilla eventually joined up with Grono as a mercenary, lying low from the Created, which wanted 589 to help them unlock more secrets of the Forerunners.