Reynolds

Reynolds was the Marine leader of a team called Fireteam Bravo that was searching for John-117's crashing point.

Biography
While his team was searching for John, he alerted Sergeant Johnson to the fact that there were Covenant enemies nearby. He then came under attack and did not respond to further radio hails.

His squad was pinned down by a Phantom commanded by a Brute Chieftain and all of his squad was killed, save for him. A Brute began to interrogate him on the location of "it" (probably the Ark, even though Reynolds would not know where that was) on a log bridge, but he did not tell them. When the Brute was about to execute him, the Master Chief intervened and saved Reynolds from certain death. Reynolds then jumped off the bridge, grabbed an Assault Rifle, and informed the Master Chief of his situation.

He may have died during the events that took place later that day.

Trivia
It is possible for the player to just let the Brute kill Reynolds and not intervene. The Brute will crack Reynold's spine and throw him off the bridge.