The Ghost of The Headhunters

The Spartan III Program. ONI recruit orphan children from recently glassed colonies, and sent them to certain death, in the hopes that their sheer number would overwhelm the enemy. Those who survive were transferred to a secret program, Codename:Headhunters.

These Headhunters are sent on highly classified mission deep behind enemy lines. While most didn't return, two particular ones stayed. Spartan A-157, and A-141.

Those who survived their assignment were reassigned to a Fireteam, except A-157 and A-141. ONI never disclose why, and we might never know.

A-157 and A-141 were the best of ONI's assassin's, surviving countless suicide missions. That is, until they did not return from a mission in 2547. Most thought they were dead, until a Fireteam discovered him, alongside the mangled body of A-141, and corpses of an entire Brute Clan