Special Operations Sub-Commander
From Halopedia, the Halo wiki
Although not much is known about this rank, it is most likely that the Special Commander Sub-Commander is a higher rank than the Special Operations Officer as evidenced by the name of the rank, and only subordinate to the higher Special Operations Commander as second-in-command of the latter that is placed in command of all the personnel and matériel of Special Operations detachment in a Covenant fleet. They are shown to wear harness in dark blueish-green.
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