From Halopedia, the Halo wiki
Team Gladius was one of the three five-member Spartan-III Gamma Company fireteams left on Onyx competing for top honors. They competed with teams Katana and Saber. When the Sentinels attacked Zone 67 and Camp Currahee, they were cut off from the others and killed by the Sentinels.
A gladius was a sword used by the Roman Empire's legionnaires. This is in keeping the same naming convention as the other known Gamma Company teams, which are named after bladed weapons.
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