Iranians Wash Away the Battle's Gore

From B14.15, The Turanians Are Overthrown. It illustrates B14.15.15–21:

B14.15.15
The war-steeds faltered, spent from battle’s strain;All worn and wounded, sore with toil and pain.
B14.15.16
The troops moved mountainward, their hearts restored;Great Rostam led them, honored as their lord.
B14.15.17
Their helms and jowshan were drenched in dust and gore;The horses’ armor gaped where battle tore.
B14.15.18
Their bodies ached, their hearts with triumph burned;Such is the way the wheel of fortune turned.
B14.15.19
So masked with blood and dust, no friend knew friend,Till washing brought confusion to an end.
B14.15.20
Breasts, feet, swords, stirrups, all were stained with gore;The slain concealed both hill and valley floor.
B14.15.21
They washed their heads and bodies of the stains;Their hearts were cleansed, their foes in heavy chains.