The event that is being presented in this picture is the way the Mongols killed prisoners.
The depiction of prisoners being buried alive upside-down suggests the notion of the Mongols' ruthlessness
What does the picture show ?
The central focus of the scene is the execution of prisoners by Mongol soldiers. This highlights the Mongols' reputation for being a fierce and warlike people who were not afraid to use violence to maintain control.
The presence of Mongol soldiers overseeing and engaging in the executions shows their dominance and power. The scene suggests that the Mongols were in complete control of the situation and that the prisoners were powerless to resist.