From Halopedia, the Halo wiki
He was a member of Zuma Squad, which was matched against Hastati Squad in an exercise of capture the flag in the final exercise of the term. Zuma squad split into three teams for the exercise, with two attempting to flank and ambush Hastadi squad and the third guarding the flag. Moulder advanced to Hastati Squad's apparent position alongside Newton and Verrelli. However, the squad fell for a trap set by Thomas Lasky who ordered Hastati to place their helmets together in a clearing. Moulder and his squad mates were "neutralized" in this ambush.
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