Fox commands the Coruscant Guard — the red-marked clones who police the capital rather than fight at the front. He appears through The Clone Wars, voiced by Dee Bradley Baker.
He is the army's internal security, and the series makes that a moral position rather than a job description. Fox arrests clones. He works to the Chancellor's office. And in "Orders" he shoots Fives dead in a Coruscant warehouse, mid-explanation, on the reasonable-sounding grounds that the man was armed and raving. It is the single most consequential trigger-pull in the animated canon and nobody in it ever learns that.
Catalogue entry. This figure has a verified record here rather than a full write-up — the encyclopedia labels its own depth instead of padding it.