The Horn Company was a specialized unit of Clones that served under Jedi General Eeth Koth during the early Clone Wars (during an episode called "Grievous Intrigue"). Most of the unit was wiped out when General Grievous boarded the ship, being taken down by Commando Droids, MagnaGuards, and Grievous himself. The few who survived, including Captain Lock, entered escape pods.
If you want to use Lock and the Horn Company, credit me as @thelorewizard or as @V3L0C1R4PT0R! ============================================= Credit for the base Phase I Clone goes to @Clonecommando1!