Circling up the wagons
Defensive formation of war wagons was fairly straightforward: war wagons were deployed into a rectangle or circle to form a makeshift fortification. However, owing to its lighter weight, the war carts of Yu Da You (俞大猷) could maintain some mobility even after a defensive circle was formed. This was very crucial to Yu Da You's war cart regiment, as Mongol horsemen were simply too fast and too unpredictable. A mobile defensive circle was a temporary defensive formation that protected the army so that it could relocate to a favourable position and deploy into a proper wagon fort.
Yu Da You drafted the following formations based on a medium sized battlegroup consisted of seven Xiao Ying (小營), or ninety-one war carts.
Battlegroup on the march: War cart battlegroup formed into a long column, with mounted scouts riding ahead and behind the formation.