The images looks doesn't interest me what interests me is the boasting rights INTELLIGENCE. The people on that mural and their level of civilization indicates an understanding of hunting and possibly animal husbandry and farming products. They had farming done these folks and animal husbandry. The Nubian guy even poached Elephants based on the horn and ivory he is carrying.
The brown folks tend to be carrying actual pottery items and seems to be from a civilization that understood ceramic making on top of farming and animal husbandry. Maybe seeing their weapons Murals will tell us which civilization had metal conquered which will blow the field open to a full blown civilization on a range of products metal based.