Koda

From Tardis Wiki, the free Doctor Who reference

The Koda were an organisation within the Sontaran Empire.

They served as the elite security branch of the Sontaran race. They were distinguished by brass armour and a silver collar. Koda members were covertly hostile to other Sontarans whilst protecting very high ranking officers, or executing important operations, but would not directly threaten other Sontarans.

Fleet Marshal Stentor may have been a member of the Koda, as he wore Koda-style armour during the Antares gambit. (PROSE: Lords of the Storm)