For those of you who didn’t know, Noble-6, the one we know and love as the protagonist of Halo: Reach (officially SPARTAN-B312), was a replacement.
The original Noble-6 was Thom-A293.
For those who don’t want to do the digging, here is the information from halo.wikia.com
> Thom-A293 was a SPARTAN-III commando who served as a member of the UNSC Navy during the Human-Covenant war. He was originally part of Alpha Company but he was eventually transferred to Noble Team. He sacrificed himself in spring 2552 to destroy a Covenant cruiser.
> Transfer to Noble Team
> At some unknown point before the spring of 2552, Thom, like other remaining members of Alpha Company, was transferred to Noble Team.
> During the Battle of Fumirole on April 22, 2552, Thom participated in an operation put together by LCDR Catherine-B320 to destroy a CCS-class battlecruiser maintaining position above a city. However, the Lieutenant Commander, who carried the tactical nuclear weapon intended to destroy the Covenant ship, was incapacitated while on her way to the objective by an enemy Banshee.
> Thom was the first to arrive where Kat was wounded, and immediately picked up the nuke and used his jetpack to fly into the battlecruiser because he did not have time to wait for additional help (in this case his teammates). Once inside the ship’s loading dock, he threw the nuke into a staging area. The nuke detonated before Thom could safely make it out, destroying the ship but killing Thom in the process.
> Both Commander Carter-A259 and Lieutenant Commander Catherine-B320 took responsibility for Thom’s death, unable to admit that his death was his own fault. The team’s commanding officer, Colonel Urban Holland, asserted that Thom died because he chose to attack Covenant forces without waiting for backup. Thom was replaced on Noble Team by SPARTAN-B312 a few months later, several weeks prior to the Fall of Reach.
> Thom was originally intended to play a larger role in Halo: Reach as a member of Noble Team, and was described to be “cowboy-like,” but, like Rosenda-A344, was ultimately cut from the game and only mentioned in the Noble Team performance reports as a now-deceased former member.
Also, Emile was a replacement too. But I’ve covered enough today.