Chariot tactics
The first depictions of four-wheeled wagons pulled by semi-domesticated onagers and other available animals come from the Sumerians.
Against infantry these fast chariots used tactics of wearing down the enemy by missile fire, deploying heavy troops and running down enemies.
The next step was towards faster chariots with spoke-wheels. Lighter wheels made lighter constructions possible. This made it feasible to outrun light infantry and other chariots. Plus the development of short composite bows that made it a devastating weapon.
Slingers and javeliners, who could counterattack and protect the other troops, had no armor protection or shield discipline. They were skirmishers, keeping out of enemy range. But the moving chariots showering them with arrows were difficult to hit so they were rendered helpless against these. The role and tactics of war chariots are often compared to tanks in modern warfare but this is disputed with scholars pointing out that chariots were vulnerable and fragile, required a level terrain while tanks are all-terrain vehicles, and thus not suitable for use in the way modern tanks have been used as a physical shock force.