Proficient in all aspects of infantry tactics as well as the basics of zero-to-low gravity aerospace combat, one of John-117's most notable skills is leadership-his ability to effectively direct operational detachments ranging in size from Spartan Fireteams to full-strength Marine battalions. It has been noted that UNSC personnel at all levels generally defer to John-117's experience and strategic intellect, oftentimes giving him a level of authority that far outstrips his actual rank.