05-032 Mendicant Bias (Earth-2042)

"And so here at the end of my life, I do once again betray a former master. The path ahead is fraught with peril. But I will do all I can to keep it stable - keep you safe. I'm not so foolish to think this will absolve me of my sins. One life hardly balances billions."

- Mendicant Bias

05-032 Mendicant Bias was a Contender unit monitor droid. It was the most advanced Forerunner droid at the time of its creation, and was charged with organizing Forerunner defense against the Flood during the parasite's assault on the galaxy. However, it would later defect to the Gravemind, who ultimately caused it to become rampant and turn against its creators.

Source

 * https://www.halopedia.org/Mendicant_Bias